Set up msbuild files to multitarget.
Create a nuspec file for the package.
Add the AsyncTargetingPack for .NET 4.0 target.
Cherry-pick changes from the NET_40 branch to make projects compile with TargetFrameworkVersion=v4.0.
Add some xml comments.
Add some xml comments.
Add some xml comments.
Remove auto-incrementing version number.
Merge pull request #4 from ZocDoc/MultiFrameworkTargeting

Multi framework targeting