Create Active flag for Projects

* Creates Active flag for Projects with default True
* Restricts display to Active projects for 
  * Projects list
  * Organizations list
  * Related projects of individual Project pages
* Creates Active flag display & edit in Admin
![projects code montage](https://f.cloud.github.com/assets/226228/725374/2ee66fb8-e062-11e2-8eec-52410c309101.jpg)
![edit project code montage](https://f.cloud.github.com/assets/226228/725373/2dabe696-e062-11e2-8a16-52d7b010dd11.jpg)