no-jira: implements database monitoring for c3p0 without c3p0 dependency in classpath and for the tomcat embedded pool

OO-449: remove all surviving @Transactional, add unit tests in groups to test them, add a missing view in IM, add unit tests to check it...

OO-449: with the changes of cache implementation, refactor the cache to have 1 unique cache and not a cache / course

OO-549: move the error message in the main controller instead of the contact controller to prevent popup in popup

OO-553: improve "StringHelper.transformDisplayNameToFileSystemName" to remove more special characters and all non-ascii characters in general

OO-347: add CSS class for details of a repository entry and more log by deployment of courses via the REST API

no-jira: fix logging in the course, the logging resource of type "node" made unique in the list of resources

OO-545 adding information about deprecated local data source / c3p0 pool and recommended jndi configuration

OO-543: add a mail meta ID for every mail package, so the batch of e-mails appear as only one e-mail in the outbox of OpenOLAT

OO-538: add some commit before sending an event via JMS (JMS can work the event in a separate thread before the producer commit its changes on the database)