Add extra Big Bang Theory Showname

Sickbeard was reporting: 
Provider gave result TBBT.S06E11.The.Santa.Simulation.720p.WEB-DL.DD5.1.H.264 but that doesn't seem like a valid result for The Big Bang Theory so I'm ignoring it
Merge pull request #11 from thomasmeeus/patch-1

Add extra Big Bang Theory Showname "TBBT"