CONN-1146: Update Primefaces Status Screens to correct styles

CSS:
* pf-override.css -- new CSS to restyle the Primefaces components on the Status screens, add responsive styles.

XHTML:
* StatusPrime.xhtml -- minor changes, including add a CSS class target used to assign the new styles.
* Dashboard.xhtml -- minor changes, including label of selectcheckbox component.

MISC:
* ui-icons_a8a8a8_256x240.png -- added to provide the Primefaces icon set in hex color #a8a8a8.