Update wording for the app stages.

https://github.com/madewithbytes/us_ignite/issues/263

The description of the app stages has been updated.
Update app form test.
Update ``app`` views tests.
Update common context processors tests.
Update events form tests.
Update events views form tests.
Update ``hub`` tests.
Update ``hub`` views tests.
Update organization views tests.
Update profile integration profiles.
Update profiles and section tests.
Add ack config file.
Add US ignite email admin.
Update local-dist settings.
Reduce the size of the grid by 80%.

https://github.com/madewithbytes/us_ignite/issues/249

Reducing the size of the grid allows to fit the full content
in smaller screens.

By using the foundation mechanics to change the ``$base-font-size``
and several of the grid measurements are expressed in ``rem`` allows
to scale the full size of the site.
Ignore psd files.
Update homepage ``slides`` imagery.

https://github.com/madewithbytes/us_ignite/issues/237
Removed bullets from the checkboxes list.

https://github.com/madewithbytes/us_ignite/issues/296
Reduced spacing between apps.

https://github.com/madewithbytes/us_ignite/issues/314
Removed ``shares`` dummy copy.