Add flexbox properties and update readme.md

[ImBobby]

It's 2014

[ImBobby]

Added missing property flex. The order is placed after display property.

[smazurov]

samesies on transform-style

[achrome]

+1 on this. Can't have recess go off with errors which shouldn't be there. It's annoying, specially if I am using recess on watch

[CLAassistant]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
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[grimreaper]

We are no longer maintaining this project and as such are archiving all PRs.