Remove superflous iostreams include from header files

[DennisOSRM]

Issue

including iostream is a code smell 😁

Benchmark Results

Benchmark	Base	PR
alias	aliased u32: 1149.5 plain u32: 1152.92 aliased double: 1192.73 plain double: 1226.24	aliased u32: 1140.04 plain u32: 1135.96 aliased double: 1191.97 plain double: 1179.31
json-render	String: 8.65366ms Stringstream: 11.9421ms Vector: 7.72664ms	String: 8.3811ms Stringstream: 11.5928ms Vector: 7.48348ms
match_ch	Default radius: 4.45105ms/req at 82 coordinate 0.0542811ms/coordinate Radius 5m: 4.44301ms/req at 82 coordinate 0.0541831ms/coordinate Radius 10m: 15.1047ms/req at 82 coordinate 0.184203ms/coordinate Radius 15m: 36.8425ms/req at 82 coordinate 0.449299ms/coordinate Radius 30m: 313.75ms/req at 82 coordinate 3.82622ms/coordinate	Default radius: 4.45681ms/req at 82 coordinate 0.0543513ms/coordinate Radius 5m: 4.42715ms/req at 82 coordinate 0.0539896ms/coordinate Radius 10m: 15.0754ms/req at 82 coordinate 0.183846ms/coordinate Radius 15m: 36.7688ms/req at 82 coordinate 0.4484ms/coordinate Radius 30m: 313.635ms/req at 82 coordinate 3.82482ms/coordinate
match_mld	Default radius: 2.83922ms/req at 82 coordinate 0.0346246ms/coordinate Radius 5m: 3.46332ms/req at 82 coordinate 0.0422356ms/coordinate Radius 10m: 10.2364ms/req at 82 coordinate 0.124835ms/coordinate Radius 15m: 25.959ms/req at 82 coordinate 0.316573ms/coordinate Radius 30m: 302.505ms/req at 82 coordinate 3.68909ms/coordinate	Default radius: 2.82378ms/req at 82 coordinate 0.0344363ms/coordinate Radius 5m: 2.7982ms/req at 82 coordinate 0.0341244ms/coordinate Radius 10m: 10.1089ms/req at 82 coordinate 0.123279ms/coordinate Radius 15m: 25.6753ms/req at 82 coordinate 0.313113ms/coordinate Radius 30m: 298.037ms/req at 82 coordinate 3.6346ms/coordinate
packedvector	random write: std::vector 11533.7 ms util::packed_vector 78341.3 ms slowdown: 6.79238 random read: std::vector 11336.6 ms util::packed_vector 33666.9 ms slowdown: 2.96975	random write: std::vector 11276.1 ms util::packed_vector 76592.5 ms slowdown: 6.79247 random read: std::vector 11239.4 ms util::packed_vector 32473.2 ms slowdown: 2.88923
route_ch	1000 routes, 3 coordinates, no alternatives, overview=full, steps=true 592.398ms 0.592398ms/req 1000 routes, 2 coordinates, no alternatives, overview=full, steps=true 374.506ms 0.374506ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=full, steps=true 758.339ms 0.758339ms/req 1000 routes, 3 coordinates, no alternatives, overview=false, steps=false 160.27ms 0.16027ms/req 1000 routes, 2 coordinates, no alternatives, overview=false, steps=false 102.934ms 0.102934ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=false, steps=false 143.359ms 0.143359ms/req 1000 routes, 3 coordinates, no alternatives, overview=false, steps=false, radius=750 160.865ms 0.160865ms/req 1000 routes, 2 coordinates, no alternatives, overview=false, steps=false, radius=750 102.698ms 0.102698ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=false, steps=false, radius=750 142.837ms 0.142837ms/req	1000 routes, 3 coordinates, no alternatives, overview=full, steps=true 596.461ms 0.596461ms/req 1000 routes, 2 coordinates, no alternatives, overview=full, steps=true 379.358ms 0.379358ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=full, steps=true 768.937ms 0.768937ms/req 1000 routes, 3 coordinates, no alternatives, overview=false, steps=false 161.377ms 0.161377ms/req 1000 routes, 2 coordinates, no alternatives, overview=false, steps=false 103.603ms 0.103603ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=false, steps=false 144.056ms 0.144056ms/req 1000 routes, 3 coordinates, no alternatives, overview=false, steps=false, radius=750 159.623ms 0.159623ms/req 1000 routes, 2 coordinates, no alternatives, overview=false, steps=false, radius=750 103.457ms 0.103457ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=false, steps=false, radius=750 144.124ms 0.144124ms/req
route_mld	1000 routes, 3 coordinates, no alternatives, overview=full, steps=true 725.171ms 0.725171ms/req 1000 routes, 2 coordinates, no alternatives, overview=full, steps=true 465.519ms 0.465519ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=full, steps=true 956.377ms 0.956377ms/req 1000 routes, 3 coordinates, no alternatives, overview=false, steps=false 283.12ms 0.28312ms/req 1000 routes, 2 coordinates, no alternatives, overview=false, steps=false 169.24ms 0.16924ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=false, steps=false 307.464ms 0.307464ms/req 1000 routes, 3 coordinates, no alternatives, overview=false, steps=false, radius=750 279.266ms 0.279266ms/req 1000 routes, 2 coordinates, no alternatives, overview=false, steps=false, radius=750 169.58ms 0.16958ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=false, steps=false, radius=750 308.413ms 0.308413ms/req	1000 routes, 3 coordinates, no alternatives, overview=full, steps=true 725.453ms 0.725453ms/req 1000 routes, 2 coordinates, no alternatives, overview=full, steps=true 466.925ms 0.466925ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=full, steps=true 952.26ms 0.95226ms/req 1000 routes, 3 coordinates, no alternatives, overview=false, steps=false 282.626ms 0.282626ms/req 1000 routes, 2 coordinates, no alternatives, overview=false, steps=false 167.719ms 0.167719ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=false, steps=false 303.848ms 0.303848ms/req 1000 routes, 3 coordinates, no alternatives, overview=false, steps=false, radius=750 281.084ms 0.281084ms/req 1000 routes, 2 coordinates, no alternatives, overview=false, steps=false, radius=750 168.693ms 0.168693ms/req 1000 routes, 2 coordinates, 3 alternatives, overview=false, steps=false, radius=750 303.77ms 0.30377ms/req
rtree	1 result: 208.76ms -> 0.020876 ms/query 10 results: 243.918ms -> 0.0243918 ms/query	1 result: 209.796ms -> 0.0209796 ms/query 10 results: 246.411ms -> 0.0246411 ms/query