Added active property on League.

Also possible to see what leagues are active, as well as changing the state on the league edit page.
Added a League selector component.

This is now used in the places where it is needed to select a league.
The leagues are now grouped by if they are active or not.
Don't know where I got commons-io 2.5 from

Use 2.4 instead, which I actually can find in maven central.
Merge pull request #40 from frankbille/issue-39

Make it possible to inactivate a league