Fixes CVE-2018-16470 and CVE-2018-16471

closes #7876

Fixes:
* CVE-2016-9318
* CVE-2017-16932
* CVE-2017-18258
* CVE-2018-14404
* CVE-2018-14567

Fixes CVE-2018-1000544

Facebook removed the API and facebook integration is broken now, so lets
remove it.

closes #7874

closes #7873

As a new, novice user, I ran into an issue where my postgresql
password contained special characters.  After a brief conversation
with DenSchub on #diaspora, it was noted that while the example
database configuration had quotes added for mysql, but not for
postgresql, and it was suggested this be improved.

closes #7875

closes #7872

Otherwise camo crashes with:
TypeError [ERR_UNESCAPED_CHARACTERS]: Request path contains unescaped characters

closes #7871

and mention /statistics and NodeInfo

closes #7867

Fallbacks are set in config/initializers/locale.rb and this settings
conflicts with the fallbacks set there.

Fixes #7860

closes #7861

Fixes #7852

closes #7853

Fixes CVE-2018-1000201

closes #7859

Fixes CVE-2018-1000539

Fixes #7854

closes #7849

closes #7839

/ was missing in the profile entity $ref

closes #7835

closes #7833

Previous file history in 80dfdcd6, couldn't keep it.

closes #7826

LinksController redirects requests for provided diaspora:// links to
respective entities urls.

This is required to make url_for(StatusMessage.new) work

closes #7830

Fixes CVE-2018-3760

closes #7829

fixes #7770

closes #7774

closes #7814

closes #7822