Merge pull request #116 from camilotorresf/fixes

Fixes for category listing
Websearch by hashtag
Merge pull request #117 from oakoval/live

Websearch by hashtag
Added fetch images animation, removed navigation buttons if it have only one image fetched
Merge pull request #118 from oakoval/live

Added fetch images animation
In category listing: load 50 items at a time
admin edit pins: paginate 50 items in category search
edit pins: change to edit with button and image

In order to allow multiple selection of items, the edition of the pin is done now through a button or the pin image.
edit pins: edit only through the button, not image.
edit pins: Select and Unselect all pins
edit pins: Button to delete selected pins
Add an option in admin to remove items from categories
Fix pagination in category selection
Add an option in admin to remove items from categories