remove "mingw" compiler

Author: jakoch

developer-manual/en/chapter01-building-fifengine-on-windows.adoc

@@ -19,20 +19,10 @@ The are several good IDEs available, including:
 
 ===== Compiler
 
-You need `msvc` or `gcc` or `mingw-gcc`. 
+You need `msvc` or `gcc`. 
 
 In case you installed MS Visual Studio, then the MSVC compiler is already installed.
 
-[IMPORTANT] 
-.gcc and mingw-gcc toolchain support is not ready, yet
-====
-In case you want to build using `gcc`, we suggest using one of the following toolchains:
-
-* http://tdm-gcc.tdragon.net/[tdragon's TDM-GCC MinGW]
-** This compiler and toolchain is also included in our Fife-SDK for MinGW.
-* http://mingw-w64.org/[MinGW-W64]
-====
-
 ===== CMake
 
 Fife uses CMake as build system. The build system generates the build configuration for the project and set the project up for your specific IDE.
@@ -67,8 +57,6 @@ You have the choice of building the dependencies from source or fetching pre-bui
 The pre-build binaries are build on-the-fly, when building Fifengine on Appveyor.
 You find MSVC 14 builds here: https://ci.appveyor.com/project/LinuxDonald/fifengine
 
-NOTE: We are working on building the dependencies on the fly using the MinGW toolchain.
-
 These builds are also included in our pre-packaged Windows development kit, 
 the https://ci.appveyor.com/project/LinuxDonald/fife-windows-sdk/branch/master/artifacts[Fife-SDK].