Fixed cmake-vs2019-win64.bat

Author: RobertBeckebans

cmake-vs2019-64bit.bat renamed to cmake-vs2019-win64.bat

@@ -2,5 +2,5 @@ REM cd ..
 del /s /q build
 mkdir build
 cd build
-cmake -G "Visual Studio 16 2019" -A x64 -DCMAKE_PREFIX_PATH="C:\Qt\5.15.2\msvc2015_64" ..
+cmake -G "Visual Studio 16 2019" -A x64 -DCMAKE_PREFIX_PATH="C:\Qt\5.15.2\msvc2019_64" ..
 pause