Update Maven, fix bugs with databases

Updated pom.xml for 1.6.2 and added IntelliJ specific folders to gitignore.

Database settings have been separated into nodes for host, port, type and name. The resulting jdbc string is build in the code. This makes it easier for people that don't know how to format a jdbc string correctly to migrate to databases. Errors while connecting to a database are now printed to console instead of being silently ignored.

Admin claims didn't transfair to the database correctly because there are areas in the code where the owner of a claim is accessed via the field instead of using the getter method. The getter method sets the field of the Claim if it's an adminclaim. Additionally the default admin name was retrieved from a DataStore before the datastore was initialized.

A few NPE's are caught correctly now and will print a human readable error to the console.


Notes:
I encountered countless unused variables and code that has been commented out while looking through the code. I assumed that most variables are kept as a reminder so I didn't remove them.

Also the database design is far from optimal and basically just the flatfile storage copied to database fields. This should be fixed before the full release.