Use Github Actions instead of Travis

Moved MSVC to Github Actions as well.

.ci/windows-msvc/build.sh

@@ -0,0 +1,8 @@
+#!/bin/sh -ex
+
+mkdir build && cd build
+cmake .. -DCMAKE_BUILD_TYPE=Release -G Ninja -DCMAKE_TOOLCHAIN_FILE="$(pwd)/../CMakeModules/MSVCCache.cmake" -DUSE_CCACHE=ON -DWARNINGS_AS_ERRORS=OFF -DUSE_BUNDLED_QT=1
+
+ninja
+# show the caching efficiency
+buildcache -s

.ci/windows-msvc/deps.sh

@@ -0,0 +1,10 @@
+#!/bin/sh -ex
+
+BUILDCACHE_VERSION="0.22.3"
+
+choco install wget ninja
+# Install buildcache
+wget "https://github.com/mbitsnbites/buildcache/releases/download/v${BUILDCACHE_VERSION}/buildcache-win-mingw.zip"
+7z x 'buildcache-win-mingw.zip'
+mv ./buildcache/bin/buildcache.exe "/c/ProgramData/chocolatey/bin"
+rm -rf ./buildcache/