(pouchdb#4207) - Add slack to places to contact us

[skip ci]

CONTRIBUTING.md

@@ -6,8 +6,7 @@ Welcome, so you are thinking about contributing to PouchDB? awesome, this is a g
 Get in Touch
 ------------
 
-The following documentation should answer most of the common questions about how to get starting contributing, if you have any questions, please feel free to ask on the
-[PouchDB Mailing List](https://groups.google.com/forum/#!forum/pouchdb) or in #pouchdb on irc.freenode.net.
+The following documentation should answer most of the common questions about how to get starting contributing, if you have any questions, please feel free to get in touch @ [Freenode IRC](https://www.irccloud.com/invite?channel=pouchdb&hostname=irc.freenode.net&port=6697&ssl=1), [Slack](http://slack.pouchdb.com),in [the Google Groups mailing list](https://groups.google.com/forum/#!forum/pouchdb), and [on StackOverflow](http://stackoverflow.com/questions/tagged/pouchdb). Or you can [tweet @pouchdb](http://twitter.com/pouchdb).
 
 Most project discussions should happen on the Mailing list / Bug Tracker and IRC, however if you are a first time contributor and want some help getting started feel free to send a private email to any of the following maintainers:
 

README.md

@@ -15,7 +15,7 @@ To get started using PouchDB, check out the [web site](http://pouchdb.com) and [
 Getting Help
 ------------
 
-The PouchDB community is active [on Freenode IRC](irc://freenode.net/#pouchdb), in [the Google Groups mailing list](https://groups.google.com/forum/#!forum/pouchdb), and [on StackOverflow](http://stackoverflow.com/questions/tagged/pouchdb). Or you can [tweet @pouchdb](http://twitter.com/pouchdb)!
+The PouchDB community is active [on Freenode IRC](https://www.irccloud.com/invite?channel=pouchdb&hostname=irc.freenode.net&port=6697&ssl=1), [Slack](http://slack.pouchdb.com),in [the Google Groups mailing list](https://groups.google.com/forum/#!forum/pouchdb), and [on StackOverflow](http://stackoverflow.com/questions/tagged/pouchdb). Or you can [tweet @pouchdb](http://twitter.com/pouchdb)!
 
 If you think you've found a bug in PouchDB, please write a reproducible test case and file [a Github issue](https://github.com/pouchdb/pouchdb/issues). We recommend [bl.ocks.org](http://bl.ocks.org/) for code snippets, because some iframe-based services like JSFiddle and JSBin do not support IndexedDB in all browsers. You can start with [this template](https://gist.github.com/nolanlawson/816f138a51b86785d3e6).