FIX: typo
FEATURE: Google Play Services v12
TEST: removed gservice ping
FIX: removed lastReceptionTime
FIX: disconnection handling
FIX: back compatibility for v2.1.5 (ping response)
FEATURE: protocol version in handshake (on GSERVICE_HANDSHAKE message)
FIX: typo
FIX: back compatibility ping response every 5 iters
CLEANUP: import auto refactoring