Added a new function for enlarging the model. Currently
has the same functionality as the previous enlarge.
Some new species in n-Heptane.
Rewrite the enlarge code to now only react species
with other species they react with in the chemkin 
file.
Merge remote-tracking branch 'victor/chemkinimporter' into chemkinimporter
AramcoMech species

Conflicts resolved:
	testcase/chemkin_importer/AramcoMech_1.3/SMILES.txt
Remove all matched cyclic species!

This is overkill, because many of these (especially the benene rings etc)
are almost certainly right. But to be safe, I removed them all with a sed script,
and we can revert (replace) the ones that are correct.