UP-4234v2: Updates to Marketplace UI

Several changes, including:
 - Moving the table filter and sorting buttons into one row;
 - Adding Bootstrap styles to filter form;
 - Making the featured tiles smaller;
 - Making the sort buttons smaller;
 - Adding some Font Awesome! icons to the UI;
 - Removing the 'Search' button (since the table is filtered live) and adding a 'Clear' button that clears the text in the search box;
 - Removed the unnecessary HTML elements created and JavaScript and wrote them as HTML in the body;
 - Fixed the issue with the sort buttons not showing active when pressed;
 - Cleaned up some CSS;

Before picture:
![marketplace_before](https://cloud.githubusercontent.com/assets/3999821/4328641/0f31bfe2-3f89-11e4-9c37-fb3adba445cf.png)

After picture:
![marketplace_after](https://cloud.githubusercontent.com/assets/3999821/4328657/25e222f4-3f89-11e4-9bdf-d4bef36ecc5f.png)

Awesome -- thanks for the catch.  I have restored this capability and tested/verified the fact that it's not related to pre-populating the search box with terms from an earlier, unrelated use of the portlet.  I'm going to complete this PR out-of-band to apply this change.