Merge pull request #20 from jd-au/stack-multiple-obs

Merge multiple observations into a set of field based observations

Use new catalogue file names

Add component_id to the spectra catalogue

Merge pull request #19 from jd-au/18-correct-beam-positions

Fix issue #18 - incorrect beam positions

Merge pull request #17 from jd-au/deduplication

Detect and exclude duplicate sources

Merge pull request #16 from jd-au/gaskap-oh

Merge in code from RadioAbsTools

Merge pull request #15 from jd-au/multiple-emission

Add support for multiple separate emission cubes

Merge pull request #14 from jd-au/galactic

Change Milky Way maps to have Galactic coordinates

Merge pull request #13 from jd-au/measure-slope