Resolve "Enable custom panel by default and have default content"

Closes #146

See merge request pleroma/pleroma!124

Elaborate on setup steps and CLI commands.

See merge request pleroma/pleroma!126

Add info about certbot with the webroot plugin to pleroma.nginx

See merge request pleroma/pleroma!125

Seems to be faster in general, query planner chooses well.

* How to use MIX_ENV

* How to create a user

* Link to certbot's site with the webform which advises how to obtain
  a certificate based on web server/OS.

TwitterAPI: Add Qvitter notification endpoint.

Closes #142

See merge request pleroma/pleroma!123

Ignore setup_db.psql and specify a folder for custom emojis

See merge request pleroma/pleroma!121

Wiki page should also be updated to recommend that admins put their custom emojis in /priv/static/emoji/custom/. This both makes for less hassle when doing a pull. And also prevents more mess in the /priv/static/emoji/ folder.

The most common case is running it on the same server.

CommonAPI post: kill \r with fire

See merge request pleroma/pleroma!120

Fix rm_user task.

See merge request pleroma/pleroma!119

MastoAPI and OAuth: allow login with either email or username.

See merge request pleroma/pleroma!118

Add rm_user mix task

See merge request !109