Trying to fix naming issue

Author: JakeGinnivan

appveyor.yml

@@ -19,7 +19,7 @@ build_script:
   - cmd: appveyor PushArtifact "build\NuGetCommandLineBuild\GitVersion.CommandLine.%GitVersion_NuGetVersion%.nupkg"
   - cmd: appveyor PushArtifact "build\NuGetRefBuild\GitVersion.%GitVersion_NuGetVersion%.nupkg"
   - cmd: appveyor PushArtifact "build\NuGetTaskBuild\GitVersionTask.%GitVersion_NuGetVersion%.nupkg"
-  - cmd: appveyor PushArtifact "build\GemBuild\gitversion-%GitVersion_SemVer%.gem"
+  - ps: appveyor PushArtifact "build\GemBuild\gitversion-$env:GitVersion_MajorMinorPatch" + (&{If($env:GitVersion_PreReleaseTag -eq '' -or $env:GitVersion_PreReleaseTag -eq $null) {""} Else {"."+$env:GitVersion_PreReleaseTag}}) + ".gem"
 
   - cmd: 7z a "GitVersion_%GitVersion_NuGetVersion%.zip" .\build\NuGetCommandLineBuild\Tools\*.*
   - cmd: appveyor PushArtifact "GitVersion_%GitVersion_NuGetVersion%.zip"