Update appveyor

Author: madhanrm

.appveyor.yml

@@ -6,10 +6,10 @@ environment:
 install:
   - echo %PATH%
   - echo %GOPATH%
-  - set PATH=%GOPATH%\bin;c:\go\bin;%PATH%
   - go version
   - go env
-
+  - ps: $webClient = New-Object System.Net.WebClient; $InstallPath="c:" ; $webClient.DownloadFile("https://raw.githubusercontent.com/jhowardmsft/docker-tdmgcc/master/gcc.zip", "$InstallPath\gcc.zip"); Expand-Archive $InstallPath\gcc.zip -DestinationPath $InstallPath\gcc -Force; $webClient.DownloadFile("https://raw.githubusercontent.com/jhowardmsft/docker-tdmgcc/master/runtime.zip", "$InstallPath\runtime.zip"); Expand-Archive $InstallPath\runtime.zip -DestinationPath $InstallPath\gcc -Force; $webClient.DownloadFile("https://raw.githubusercontent.com/jhowardmsft/docker-tdmgcc/master/binutils.zip","$InstallPath\binutils.zip"); Expand-Archive $InstallPath\binutils.zip -DestinationPath $InstallPath\gcc -Force; 
+  - set PATH=%GOPATH%\bin;c:\go\bin;c:\gcc\bin;%PATH%
 build: off
 
 test_script: