Ease contribution

[embix]

• remove workitem mentions from code
• clean up code comments
• set license to MIT, mention Licenses of linked/distributed stuff
• build script should actually build, currently only creates package from VS generated build
• provide sample project: see https://github.com/questnet/FSCS-LensgeneratorSample
• running in VS should take that sample project as input an generate
• Tests, running on sample project should generate lenses as expected
• command line reference in readme
• step-by-step guide from clone to usable build
• configure continuous integration with appveyor
• contribution guide in readme
• provide nuget packages via feed (myget, nuget gallaery once the project more mature)
• streamline workflow from pullrequest to release - still too much to do

once the project is ready:

• announce the Lensgenerator