Show finished projects

I added the "tab" closed projects to the desktop, similary to the closed task view:

![image](https://cloud.githubusercontent.com/assets/5181475/4808012/4b23dfb8-5e9b-11e4-99ed-c95ca2042b6c.png)

The list contains only the last 10 closed projects assigned to the current user, so that the desktop page doesn't load slower when the number of closed project increases:

![image](https://cloud.githubusercontent.com/assets/5181475/4808162/76eaf152-5e9d-11e4-97ee-1b02cdf75aa8.png)

At the end of the list is a new link "All closed projects" which links to the new page manageclosedprojects.php. This page lists all closed projects:

![image](https://cloud.githubusercontent.com/assets/5181475/4808195/c7c15206-5e9d-11e4-98de-e03595f4e7b1.png)