removed all superfluous operations from GMOSPrepare. Moving on to CutSlits
fixed the GMOSPrepare and split off the slit cutting
added chip gap information
finished preliminary implementation of mask cutting
Merge branch 'master' into gmos/split_up_slit_cutting

Conflicts:
	geminiutil/gmos/gmos_basics.py
Merge pull request #25 from wkerzendorf/gmos/split_up_slit_cutting

Gmos/split up slit cutting