added README-dev section on contributing code
added README-dev section on contributing code

couchbaselabs/cbft,nimishzynga/cbgt,nimishzynga/cbgt,couchbaselabs/cbft,steveyen/cbft,nimishzynga/cbgt,nimishzynga/cbgt,steveyen/cbft,steveyen/cbft,steveyen/cbft,couchbaselabs/cbgt,couchbaselabs/cbgt,couchbaselabs/cbft,steveyen/cbft,couchbaselabs/cbgt,couchbaselabs/cbft,couchbaselabs/cbgt