Ticket 602: Add GEMINI button to each slice on home page.
Ticket 602: Add GEMINI button to each slice on home page.

Note that a link still needs to be provided to general genidesktop
page.

tcmitchell/geni-portal,charliemeyer/geni-portal,tcmitchell/geni-portal,tcmitchell/geni-portal,charliemeyer/geni-portal,tcmitchell/geni-portal,charliemeyer/geni-portal,charliemeyer/geni-portal,charliemeyer/geni-portal,tcmitchell/geni-portal