[Mac] Keyman for Mac does not work correctly with Atom Editor

<a href="https://github.com/mcdurdin"><img src="https://avatars2.githubusercontent.com/u/4498365?v=3" align="left" width="96" height="96" hspace="10"></img></a> **Issue by [mcdurdin](https://github.com/mcdurdin)**
_Sunday Feb 26, 2017 at 00:44 GMT_
_Originally opened as https://github.com/sillsdev/keyman/issues/31_

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Reported by @andjc 

(SublimeText and TextEdit are fine)
