added GMOSFilter class that works with the filters
added new filter data
added GMOSGrating to the Database .. working on InstrumentSetup.
renamed chip1_detector
finished implementing GMOSMOSInstrumentSetup .. now for the reading in
properly reading in GMOSMOSInstrumentSetup
nearly done with instrument setup.
Merge pull request #9 from wkerzendorf/gmos/instrument_setup

Added an instrument setup with filters and gratings to the gmos raw fits object