Use semver 2.0 for pre-release packages

Author: natemcmaster

version.props

@@ -7,9 +7,10 @@
     <BuildNumber Condition=" '$(BuildNumber)' == '' ">$(APPVEYOR_BUILD_NUMBER)</BuildNumber>
     <BuildNumber Condition=" '$(BuildNumber)' == '' ">0</BuildNumber>
     <FileVersion>$(VersionPrefix).$(BuildNumber)</FileVersion>
-    <VersionSuffix Condition=" '$(VersionSuffix)' != '' ">$(VersionSuffix)-00$(BuildNumber)</VersionSuffix>
+    <VersionSuffix Condition=" '$(VersionSuffix)' != '' ">$(VersionSuffix).$(BuildNumber)</VersionSuffix>
 
     <BranchName Condition=" '$(BranchName)' == '' ">$(APPVEYOR_REPO_BRANCH)</BranchName>
+    <VersionSuffix Condition=" '$(VersionSuffix)' != '' AND '$(BranchName)' != '' ">$(VersionSuffix)+$(BranchName)</VersionSuffix>
   </PropertyGroup>
 
   <ItemGroup>