Change boost sprite to look like fa-retweet

Fix S3 default settings

application website validation, don't link to app website if website isn't set,
also comment out animated boost icon from #464 until it's consistent with non-animated version

Make boost button spin around

Add a 'Back to Mastodon' link to footer of settings pages

Hide 'Do not display on public timeline' for reply toots

with YAML-defined defaults. Add admin page for editing global settings. Add "site_description"
setting that would show as a paragraph on the frontpage

fix Vagrantfile so that the correct ruby is installed

Prior to this commit, the vagrantfile installs ruby 2.3.3. Due to commit mastodon@7951e7f, this no longer works.

Change the provision scrip so that 2.3.1 is installed via rbenv. Note this drastically increases provision time.

fix bug in process feed service

Fix repo URL

simplify emojification on public pages with .emojify class