- update copyright

- add instructions for cross-compilation
- add utility function for Windows and Linux executable path

docs/COMPILATION.md

@@ -0,0 +1,31 @@
+# Cross Compiling with MinGW 64
+
+
+As I do not own any Windows machine, builds on Windows rely on [MinGW](https://www.mingw-w64.org) which is install with the ArchLinux package group `mingw-64-toolchain` (contains [MinGW64 Crosscompilation parts](https://archlinux.org/packages/?q=mingw-w64))
+
+## Install MinGW
+
+```bash
+pacman -S mingw-w64-toolchain
+```
+
+## Create Build
+
+The root folder adds a `.gitignore` rule to leave out everything `build*`
+
+```bash
+mkdir -p build_w64
+cd build_w64
+```
+
+## Configure
+
+```bash
+cmake . -DCMAKE_TOOLCHAIN_FILE=../etc/cmake/mingw64-toolchain.cmake
+```
+
+## Build
+
+```bash
+cmake --build .
+```