Added to lists and added conversions

Added chemicals to parameter group lists.  Added alkalinity conversions, bicarbonate conversions, carbonate conversions, and nitrate nitrite conversions.
wording changes
Merge branch 'patch-3' of git://github.com/inkenbrandt/ugs-chemistry into inkenbrandt-patch-3
get line lengths under control
Merge branch 'inkenbrandt-patch-3' into preprocessing

fixes #9