Merge pull request #1197 from akoeplinger/remove-csproj

[Cleanup] Removed a bunch of superfluous .csproj and .sln files
Fixed issue related to fully qualified namespaces being used for XmlEnumAttribute values.
Merge pull request #1198 from chriswebb/master

Fixed issue where XmlReflectionImporter unable to handle XmlEnums with colons
Removed [Category("NotWorking")] from PackUriHelperTests.
CompareInvalidTest is still not working because .NET PackUriHelper.ComparePackUri is doing something that uses Uri and throws an exception whereas Mono is not.
Changed Check.PartUriIsValid to throw ArgumentException.
Added argument validations to ComparePackUri an ComparePartUri.
Merge pull request #1199 from esdrubal/packurihelper

PackUriHelper
[mcs] null propagating operator with nested receiver
[Cleanup] Removed .jvm.cs files that are no longer used

They were once part of a special Java target profile, but this is no longer used today.
[Cleanup] Removed net_1_1_java*.sources files
[Cleanup] Removed net_1_1_java from Makefiles
[Cleanup] Removed JavaEE csproj and sln files
[Cleanup] Removed files that imported Java namespaces
[Cleanup] Removed TARGET_JVM