Initial Maven setup.

* compilation via maven.
* unit testing currently disabled from maven; needs restructuring.
* empty plugin localisation file.
Support automatic unit testing via Maven.

* Tests where moved to separate source folder (layout does still not conform to maven guidelines).
* Removed (again) JUnit plug-in dependency in manifest file.
Removed now unnecessary exclusion.

The exclusions are not necessary any more because the benchmarks and tests were moved from the 'src' to the 'test' folder.
Adding required line break at the end of the file.
Including non-Java resources from source folder.

This is necessary because the project doesn't follow the Maven folder structure.
Removing build artefacts because they should not appear in source folders.
Several minor changes to the type checking code
Merge branch 'master' of github.com:cwi-swat/rascal
Fixed problem in Tutor due to name change of constructors in Rascal
grammar
fixed direct use of fast ValueFactory to prevent future wtf's.
Fixes in RascalTutor and Courses
Fixes to Courses
jsonread and jsonwrite added
jsonread and jsonwrite added
Merge branch 'master' of https://github.com/cwi-swat/rascal
Removed override annotation from a method in JDBC. Since in it caused compile errors.
Fixed more inconsistencies in the course files.
Merge branch 'master' of github.com:cwi-swat/rascal
Added missing documentation
-Updated comments.