Add option to disable hostname check (#399)

* Suppress compiler warnings about unused elements.

* Enable CMake's compilation database.

* Add TLS option to disable checking a certificate's host name.

* Add `--disable-hostname-validation` to `ws`.

* Add test for disabling hostname validation.

CMakeLists.txt

@@ -11,6 +11,7 @@ project(ixwebsocket C CXX)
 set (CMAKE_CXX_STANDARD 11)
 set (CXX_STANDARD_REQUIRED ON)
 set (CMAKE_CXX_EXTENSIONS OFF)
+set (CMAKE_EXPORT_COMPILE_COMMANDS yes)
 
 option (BUILD_DEMO OFF)