Add TravisCI configuration
Add TravisCI configuration

Currently 5 matrix cells:
  - Rust server on Rust stable
  - Rust server on Rust beta
  - Rust server on Rust nightly
  - C++ server on Clang 3.8
  - C++ server on GCC 5

LoungeCPP/Tatsoryk,LoungeCPP/Tatsoryk,LoungeCPP/Tatsoryk,LoungeCPP/Tatsoryk