Media grid catch up

Finally figured out how to separate out those first two commits!

These two commits comprise the 3 main files for wp-media-grid-view as seen on wordpress.org plugin respository.  Sorry it was my first time and I didn't fully understand the commit process than (still don't ha!) so I only committed the main wp-media-grid.php file on the first one neglecting scripts.js and style.css which are in the second commit.