Removed not so useful function BeamFitter::formatBTime() which made
char ts[] a static because otherwise the function returns the address of
a function temporary. This function was only called by BeamFitter::updateBTime,
which was changed to produce the same results: format two GMT times as strings
and put the results in a member variable.
Merge pull request #2135 from gartung/RecoVertex-BeamSpotProducer-remove-static-ts

RecoVertex Fixes -- Removed not so useful function BeamFitter::formatBTime()