might as well be consistent and use the 'ref' parameter everywhere instead of 'f_ref'

We'd sort of decided to remove f_ from all the external parameters (not for the variable names) anyway

git-svn-id: http://mantisbt.svn.sourceforge.net/svnroot/mantisbt/trunk@1617 <a class="text" href="/?p=mantisbt.git;a=object;h=f5dc347c">f5dc347c</a>-c33d-0410-90a0-b07cc1902cb9