gvite-v1.1.2-release

Gvite-v1.1.2 release, with following new features:

1. Fast fail if config file is not parsed correctly during gvite start.
2. Latency statistics for block propagation.

SHA256(gvite-v1.1.2-darwin.tar.gz)= 4cb407ce1c1528e6727a8bc9b9420e75a98dffaff0c1f3f3539b1fb497da5f98
SHA256(gvite-v1.1.2-linux.tar.gz)= bb9b87a9902a31907b05be478253213746f3641d7472baee77deae77c8233d5a
SHA256(gvite-v1.1.2-windows.tar.gz)= 3f22cce523c0f7e6996e8e49da481d8c04db7567b8a86e01ec87048b07a3a4f2