Updates AppVeyor build matrix

Author: j-ulrich

.appveyor.yml

@@ -3,18 +3,22 @@ version: "{build}"
 environment:
     CTEST_OUTPUT_ON_FAILURE: '1'
     matrix:
-        - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
+        - CMAKE_GENERATOR: Visual Studio 15 2017
+          QT_DIR: C:\Qt\5.11\msvc2017_64
+          APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
+          VCVARS_COMMANDLINE: '"C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Auxiliary\Build\vcvars64.bat"'
+        - CMAKE_GENERATOR: Visual Studio 14 2015
+          QT_DIR: C:\Qt\5.9\msvc2015
+          APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
           VCVARS_COMMANDLINE: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat" x86'
-          CMAKE_GENERATOR: Visual Studio 14 2015
-          QT_DIR: C:\Qt\5.8\msvc2015
-        - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
-          VCVARS_COMMANDLINE: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat" x86'
-          CMAKE_GENERATOR: Visual Studio 14 2015
+        - CMAKE_GENERATOR: Visual Studio 14 2015
           QT_DIR: C:\Qt\5.6\msvc2015
-        - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2013
+          APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
+          VCVARS_COMMANDLINE: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat" x86'
+        - CMAKE_GENERATOR: Visual Studio 12 2013
+          QT_DIR: C:\Qt\5.6\msvc2013
+          APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2013
           VCVARS_COMMANDLINE: '"C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\vcvarsall.bat" x86'
-          CMAKE_GENERATOR: Visual Studio 12 2013
-          QT_DIR: C:\Qt\5.8\msvc2013
 
 before_build:
     - call %VCVARS_COMMANDLINE%