Better support for preview tags

src/Microsoft.NET.Sdk.Functions.MSBuild/Targets/netstandard1.0/Microsoft.NET.Sdk.Functions.Build.targets

@@ -21,7 +21,7 @@ WARNING:  DO NOT MODIFY this file unless you are knowledgeable about MSBuild and
   <Target Name="_GenerateFunctionsPostBuild"
           AfterTargets="Build">
     <PropertyGroup>
-      <UseNETCoreGenerator Condition="$(UseNETCoreGenerator)=='' AND ($(AzureFunctionsVersion) == 'v2' OR $(AzureFunctionsVersion) == 'v2-prerelease' )">true</UseNETCoreGenerator>
+      <UseNETCoreGenerator Condition="$(UseNETCoreGenerator)=='' AND $(AzureFunctionsVersion.StartsWith('v2'))">true</UseNETCoreGenerator>
     </PropertyGroup>
     <!-- TODO: CopyFilesToOutputDirectory does not look at the outdir to copy the pdbs. hence copying it manually. -->
     <!-- Copy the application pdb to the bin folder-->

src/Microsoft.NET.Sdk.Functions.MSBuild/Targets/netstandard1.0/Microsoft.NET.Sdk.Functions.Version.props

@@ -11,7 +11,7 @@ WARNING:  DO NOT MODIFY this file unless you are knowledgeable about MSBuild and
 <Project ToolsVersion="14.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
 
   <PropertyGroup>
-    <FunctionsSdkVersion>1.0.29</FunctionsSdkVersion>
+    <FunctionsSdkVersion>1.0.30-beta1</FunctionsSdkVersion>
   </PropertyGroup>
 
 </Project>

src/Microsoft.NET.Sdk.Functions.MSBuild/Targets/netstandard1.0/Microsoft.NET.Sdk.Functions.targets

@@ -72,7 +72,7 @@ WARNING:  DO NOT MODIFY this file unless you are knowledgeable about MSBuild and
  -->
   <Target Name="_InitializeFunctionsSdk">
     <Warning Text="The ExtensionsMetadataGenerator package was not imported correctly. Are you missing '$(_ExtensionsMetadataGeneratorTargetsPath)' or '$(_ExtensionsMetadataGeneratorPropsPath)'?"
-             Condition="($(AzureFunctionsVersion) == 'v2' OR $(AzureFunctionsVersion) == 'v2-prerelease') And ('$(_ExtensionsMetadataGeneratorTargetsImported)' == '' Or '$(_ExtensionsMetadataGeneratorPropsImported)' == '')" />
+             Condition="$(AzureFunctionsVersion.StartsWith('v2')) And ('$(_ExtensionsMetadataGeneratorTargetsImported)' == '' Or '$(_ExtensionsMetadataGeneratorPropsImported)' == '')" />
   </Target>
 
 </Project>