Add Microsoft.VisualBasic.Compatibility dll

[alesliehughes]

If accepted, Ill add the rest of class/enums over time.

[monoadmin]

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[migueldeicaza]

Let me recommend that this work be done independently of Mono.

Otherwise your work will have to be synchronized with ours. Also, that way you get more people to contribute to your effort and to try the assemblies at a faster rate than we can.

[alesliehughes]

I happy to contribute the whole module, at what point would you accept it into the repository?