Add community guidelines/CoC

Fixes #3484

Author: syl20bnr

COMMUNITY.org

@@ -0,0 +1,42 @@
+* For the Contributors:
+- This community is an hacker community based on meritocracy and volunteering.
+  Be good in what you bring to the project, be it code, documentation, typo
+  fixes, art, humor, ideas, project management, assurance quality, mentorship,
+  you name it! We like to award achievements to people making a difference in
+  various domains, [[file:./doc/DOCUMENTATION.org#specials][see it for yourself]]. Why not you? Make history!
+- Think you are not good enough? Find support and mentors by chatting on Gitter
+  with fellow Spacemacs users or just open an issue on GitHub, you will find
+  help to concretise your desire of contribution.
+- Mandatory: Be positive and/or with good intentions.
+* For the Users:
+- Any question related to the project is welcomed, the worst thing that can
+  happen is that we redirect you to the documentation.
+- Any opinion on the project is valorized given it is constructive.
+* The Maintainer (@syl20bnr)
+Can:
+- on GitHub, push to the repository without making a PR,
+- on GitHub, lock any discussion which seems inappropriate,
+- on Gitter, remove from the channel any member acting like a jerk,
+Can but won't:
+- on GitHub, delete or edit any message,
+- on GitHub, reject any PR without an explanation,
+- on GitHub, revert any commit without an explanation,
+- on Gitter, delete any message,
+Cannot:
+- on GitHub, ban people.
+* The Collaborators (@TheBB, @StreakyCobra)
+Can:
+- on GitHub, push to the repository without making a PR,
+Can but won't:
+- on GitHub, delete or edit any message,
+- on GitHub, reject any PR without an explanation,
+- on GitHub, revert any commit without an explanation,
+Cannot:
+- on GitHub, lock any discussion which seems inappropriate,
+- on GitHub, ban people,
+- on Gitter, remove from the channel a member,
+- on Gitter, delete any message.
+* Moderation actions
+For transparency any moderation action is recorded here.
+- syl20bnr: locked issue #3484 on 2016/01/27
+- syl20bnr: unlocked issue #3484 on 2016/01/27