Fixed bug in langs_arsort() which arose when the locale was set to one in which the decimal separator was represented by a comma.   In those circumstances the cast of a float to a string and back to a float again does not get you back to where you started.   Langs_arsort() is in fact unnecessary as it is trying to preserve the original order in a sort when two languages have the same quality value.    However in the unlikely event that a browser does specify two languages with the same quality value it presumably means that the order is unimportant.   The function langs_arsort() has therefore been removed and replaced by calls to arsort() using the SORT_NUMERIC flag.   See also SF Support Requests #649.

git-svn-id: http://svn.code.sf.net/p/mrbs/code/mrbs/trunk@2902 25f7e783-145e-4f2d-a9f8-dd7182bfe9c7