extended parser and typechecker util to make it easiere to call. multifile extension
improved type checker message for reduced visibility. Now it also displays the visibility diff
added ignore to test case. It is unknown what the test case is supose to test. Id?
updated the examples test to do proper file fetching. Note that a String source is not sufficient for the parser, since all errors will be reported with a location in the merged string making it very difficult to backtrack the line number.

There is also a flag to remove the path from file names which is enabled. This makes error comparison possible.
fixed errors in examples. @pglvdm should check if the changes made here are correct and update the CashDispencerConc model to use normal threads
removed unused imports and fixed lib testing