use "CONVERT TO" to change the encoding for the table and all character columns

First iteration to update Help section

Changes from Fla

mysql changes the type of TEXT columns to MEDIUMTEXT with "CONVERT TO",
but we don't want this, so change this columns back to TEXT.

see: https://bugs.mysql.com/bug.php?id=31291

see: https://dev.mysql.com/doc/refman/5.6/en/charset-conversion.html

This prevents connecting to the database on rake assets:precompile,
which fails in certain build environments.

Running git blame on this and figuring out what in gods name this
is for, is for another time.

Refactor available services settings

Return 406 on people/guid/contacts, format json

Add link to custom splash page wiki examples

Limited post content excluded from subject of comment email

Fix only sharing flag for contacts that are receiving

Disable auto follow back on aspect deletion

Use test instead of match wherever possible

Move default_url_options to application.rb

Don't add mentions and reshares to all streams