Merge project_grid and collection_grid into a single template

[bromagosa]

Merge project_grid and collection_grid into a single template

[bromagosa]

So that I don't forget on Monday:

project.tmp has been refactored to use a common grid.tmp for both collections and projects.

I need to look for all templates using:

project_grid.tmp
user_grid.tmp
collection_grid.tmp

and refactor them to use the new generic grid.

Also, search_bar.tmp needs to go in favor of grid.tmp with param $withSearch=true. Look for all templates using it and refactor them (this should be very easy.)

[bromagosa]

Only missing: refactor collection.tmp to use new generic grid template. Then think of further refactoring of the grid methods. Now that things are cleaner everything is becoming easier :)