Unittests

Added (most) of the unit test from 2.1.7 ch.elexis_test

Missing are
* FixMediDisplayTest.java
* Test_DBUpdate.java 
* Test_SqlWithUiRunner.java
* mvn does not yet run the PDE-Tests (same problem as in importer.div.tests)

Updated also juno.target to adapt to new location of elexis.3rdparty.libraires to be able to have there also snapshot and versions.

Also a small fix for clear error-message in case you have a problem with CoreOperationExtensionPoint