- simplified AppVeyor configuration

Visual Studio 2015 and 2019, Release only, no more WinXP toolset, reorder targets by importance
Visual Studio 2017 builds are now verified by Travis only

.appveyor.yml

@@ -6,37 +6,23 @@ branches:
 
 clone_depth: 10
 
+image:
+  - Visual Studio 2019
+  - Visual Studio 2015
+
 environment:
   matrix:
-    - GENERATOR: "Visual Studio 14 2015"
-      CONFIGURATION: Release
-      TOOLSET: v140_xp
-      APPVEYOR_BUILD_WORKER_IMAGE: "Visual Studio 2015"
-    - GENERATOR: "Visual Studio 14 2015 Win64"
-      CONFIGURATION: Release
-      TOOLSET: v140
-      APPVEYOR_BUILD_WORKER_IMAGE: "Visual Studio 2015"
-    - GENERATOR: "Visual Studio 15 2017"
-      CONFIGURATION: Release
-      TOOLSET: v141_xp
-      APPVEYOR_BUILD_WORKER_IMAGE: "Visual Studio 2017"
-    - GENERATOR: "Visual Studio 15 2017 Win64"
-      CONFIGURATION: Release
-      TOOLSET: v141
-      APPVEYOR_BUILD_WORKER_IMAGE: "Visual Studio 2017"
-    - GENERATOR: "Visual Studio 15 2017 Win64"
-      CONFIGURATION: Debug
-      TOOLSET: v141
-      APPVEYOR_BUILD_WORKER_IMAGE: "Visual Studio 2017"
-
+    - ARCH: x64
+    - ARCH: Win32
+
 build_script:
   - md build
   - cd build
-  - cmake -G "%GENERATOR%" -T "%TOOLSET%" -DPK3_QUIET_ZIPDIR=YES ..
-  - cmake --build . --config "%CONFIGURATION%" -- -maxcpucount -verbosity:minimal
+  - cmake -A %ARCH% -DPK3_QUIET_ZIPDIR=YES ..
+  - cmake --build . --config Release -- -maxcpucount -verbosity:minimal
 
 after_build:
-  - set OUTPUT_DIR=%APPVEYOR_BUILD_FOLDER%\build\%CONFIGURATION%\
+  - set OUTPUT_DIR=%APPVEYOR_BUILD_FOLDER%\build\Release\
   - 7z a ..\gzdoom.zip "%OUTPUT_DIR%gzdoom.exe" "%OUTPUT_DIR%*.pk3"
 
 artifacts: