Rewrite Location Api Code

[rleh]

• Transfer Location Api specific code to a separate class(es)
• Do not depend on Googles Play Location Service
• Check for GMS (Google Play Services), else use AOSP Location Service
• Optional: User setting: Google Play Location Service or Android Location Service
• Optional: Build type/flavor without GMS dependencies (for F-Droid)

[rleh]

Solves #89, #63 and #57