Merge pull request ethereum#2083 from ethereum/code-owners-add-josh

Add Josh to CODEOWNERS

Author: samajammin

.github/CODEOWNERS

@@ -5,7 +5,7 @@
 
 # These owners will be the default owners for everything in
 # the repo. Unless a later match takes precedence,
-*       @samajammin @ryancreatescopy
+*       @samajammin @ryancreatescopy @jjmstark
 
 # Owners of specific files
 /src/data/eth2-bounty-hunters.csv @lsankar4033 @djrtwo