Changing how items title is handled

Moving title handler from  from shortcode’s user_media() method to
template’s display()
Simplifying shortcode processing

All the confusing lifting regarding user_id and username now is done on
the end: API’s user_media() method
Dashboard's profile now handles user_id variable

Dashboard's profile now handles user_id variable properly
Removing #feed-title

We’re using the already built in .wp-ig.instagram-items-title from now
on
Adding tag title for instagram-items-title
Simplifying profile page, use $_REQUEST