[appveyor] test meson build

appveyor.yml

@@ -0,0 +1,19 @@
+image: Visual Studio 2019
+
+install:
+  # Set paths to dependencies (based on architecture)
+  - cmd: if %arch%==x86 (set PYTHON_ROOT=C:\python37) else (set PYTHON_ROOT=C:\python37-x64)
+  # Print out dependency paths
+  - cmd: echo Using Python at %PYTHON_ROOT%
+  # Add necessary paths to PATH variable
+  - cmd: set PATH=%cd%;%PYTHON_ROOT%;%PYTHON_ROOT%\Scripts;%PATH%
+  # Install meson and ninja
+  - cmd: pip install ninja meson
+  # Set up the build environment
+  - cmd: "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvarsall.bat" %arch%
+
+build_script:
+  - cmd: echo Building on %arch% with %compiler%
+  - cmd: meson --backend=ninja builddir
+  - cmd: ninja -C builddir
+