Build/GCC: Enforce version 4.7.2

(cherry picked from commit ede8f0ca0a28d059c1356c6970ac87f53c72a424)

cmake/compiler/gcc/settings.cmake

@@ -1,7 +1,7 @@
 # Set build-directive (used in core to tell which buildtype we used)
 add_definitions(-D_BUILD_DIRECTIVE='"${CMAKE_BUILD_TYPE}"')
 
-set(GCC_EXPECTED_VERSION 4.7.2)
+set(GCC_EXPECTED_VERSION 4.9.0)
 
 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS GCC_EXPECTED_VERSION)
   message(FATAL_ERROR "GCC: TrinityCore requires version ${GCC_EXPECTED_VERSION} to build but found ${CMAKE_CXX_COMPILER_VERSION}")