Gb ios app release checklist 58387050

As an iOS Developer, I want to get our Release Checklist setup in GitHub. 
https://www.pivotaltracker.com/story/show/58387050

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Hey Alex,

Recommend looking at the output of this one, rather than the diff - it's a bit confusing.

Intended to serve as a pre-release checklist for us that could be forked for each release that we complete. 

Cheers,

G

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