Merge pull request #43 from crawfordsm/resmatch

Improve line matching for low res gratings
Merge pull request #44 from crawfordsm/resmatch

update to spectools
Updates to saltfirst taks
Update to saltclean.py
Merge branch 'master' of https://github.com/saltastro/pysalt
update of amp values
adding Xe.salt
Update to the lines