Now reads UCAC4 catalog location from config file.  Remove tests for self.coordinate_header as they no longer seem to work with some versions of astropy?
Merged stuff on altair with github.  Did not properly do diff, but should be nothing of consequence on altair, I hope.
Resolve conlfist from previous commit.
Merge branch 'feature/overplot_catalog' of https://www.github.com/joshwalawender/IQMon into feature/overplot_catalog
Merge branch 'feature/overplot_catalog' of https://www.github.com/joshwalawender/IQMon into feature/overplot_catalog