Add test for C# based on Java example to test strings in and out. Memory cleanup for Java test.
git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@7175 626c5289-ae23-0410-ae9c-e8d60b6d4f22
git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@6355 626c5289-ae23-0410-ae9c-e8d60b6d4f22