fix link to bug reports
Merge pull request #2830 from eksperimental/patch-1

fix link to bug reports
explaining #elixir-lang

the markdown parser doesn't recognize the irc:// link, so it's not clear what #elixir-lang is. (it actually looks more like a twitter hashtag)
explaining #elixir-lang (better option)

i like this one better
Merge pull request #2831 from eksperimental/patch-1

making #elixir-lang more clear
Merge branch 'master' of https://github.com/elixir-lang/elixir