Support for <Aliases> across all the <ProjectReference>.
Merge pull request #32 from SickheadGames/alias

More <Aliases> Support
Change format of reference aliasing to support platform conditionals
Implemented services and dependencies system and testing framework
Exclude service-aware projects that aren't generated from solution
Fix issue with disabling services and add more test coverage
Using services now infers a reference unless <InferReference>False</InferReference> is used

Also added an example set up of MonoGame using services in the test suite
Added test for cstools-style setup
Added cocos2d-xna style setup into test suite and implemented services adding references
Add tests for <IncludeServices> and <ExcludeServices> tags
Fix issue with Mono not allowing C# extension methods in XSLT
Handle files conditional on services correctly in the synchroniser
Ignore spec cache, remove repositories.config
Allow tests to work on Linux
Fix issue on Linux where an absolute path would be treated as an option
Detect invalid options and update help text
Built latest version of Protobuild
Fix an issue where services were not implied by references
Format and document Actions.cs
Update documentation of more files