Change the allocation for the THashList from

fKeys       = new THashList(100,4)
to
fKeys       = new THashList(100,50)
The previous allocation was generating too many TList in case the number
keys is very large.


git-svn-id: http://root.cern.ch/svn/root/trunk@4280 27541ba8-7e3a-0410-8455-c3a389f83636