remove redundant winodows build scripts

Author: kristjanvalur

.travis.yml

@@ -20,12 +20,12 @@ jobs:
       name: x64_msvc
       script:
         - cd vs2017
-        - ./build_x64.cmd && x64/Debug/test.exe
+        - ./build.cmd x64 && x64/Debug/test.exe
     - os: windows
       name: x86_msvc
       script:
         - cd vs2017
-        - ./build_x86.cmd && Win32/Debug/test.exe
+        - ./build.cmd x86 && Win32/Debug/test.exe
     - os: windows
       name: arm_msvc
       before_install: choco install --force VisualStudio2017-workload-vctools --params"--add Microsoft.VisualStudio.Component.VC.Tools.ARM"