Documentation for labeling strategy - SDI-808
Documentation for labeling strategy - SDI-808

* Consolidated repetitive types, especially enhancement and feature since we continue to fall into the trap of arguing which is which when we treat both similarly during sprints. TL;DR - we're good with just feature requests
* Mapped all metadata tags to the same color and applied them to open issues (all are #dddddd)
* Adding this information to CONTRIBUTING

sandlbn/snap,mkleina/snap,intelsdi-x/snap,sandlbn/snap,mkleina/snap,intelsdi-x/snap,mjbrender/snap,mjbrender/snap