ci: appveyor build for windows

appveyor.yml

@@ -0,0 +1,45 @@
+environment:
+  CMAKE_INSTALL_ROOT: C:\projects\cmake
+  PACKAGE_INSTALL_ROOT: C:\projects\pir
+  PKG_CONFIG_PATH: C:\projects\pir\lib\pkgconfig
+  matrix:
+    - build_name: mingw73_32_qt5_12_6
+      QTPATH: C:\Qt\5.12.6\mingw73_32
+      MINGW32: C:\Qt\Tools\mingw730_32
+
+install:
+  - mkdir %CMAKE_INSTALL_ROOT%
+  - mkdir %PACKAGE_INSTALL_ROOT%
+  - cd %APPVEYOR_BUILD_FOLDER%
+  - git submodule update --init --recursive
+  - set PATH=%PATH%;%CMAKE_INSTALL_ROOT%;%QTPATH%\bin;%MINGW32%\bin
+
+build_script:
+# prepare
+  - mkdir 3rdparty
+  - cinst ninja
+  - cinst pkgconfiglite
+# build taglib
+  - cd 3rdparty
+  - git clone -q https://github.com/taglib/taglib.git
+  - cd taglib
+  - cmake -G "Ninja" . -DCMAKE_INSTALL_PREFIX=%PACKAGE_INSTALL_ROOT% -DBUILD_SHARED_LIBS=ON
+  - cmake --build .
+  - cmake --build . --target install
+  - cd %APPVEYOR_BUILD_FOLDER%
+  - tree %PACKAGE_INSTALL_ROOT% /f
+# finally...
+  - mkdir build
+  - cd build
+  - cmake .. -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release -DCMAKE_MAKE_PROGRAM=mingw32-make -DCMAKE_INSTALL_PREFIX='%cd%'
+  - mingw32-make
+  - mingw32-make install
+# fixme: I don't know how to NOT make the binary installed to the ./bin/ folder...
+  - cd bin
+  - windeployqt --verbose=2 --no-quick-import --no-translations --no-opengl-sw --no-angle --no-system-d3d-compiler --release .\pmusic.exe
+  - xcopy /s %PACKAGE_INSTALL_ROOT%\bin %cd%
+# for debug..
+  - tree /f
+
+artifacts:
+  - path: build\bin