Removed reax/c time-averaging. Replaced integers with chemical symbols in pair_coeff command for reax/c (this actually happended on 2/25/2013, but should have happened now).

git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@9559 f3b2605a-c512-4ea7-a41b-209d697bcdaa