Change the twitter `/favorites` to `/likes`

Signed-off-by: Rémy Coutable <remy@rymai.me>

Replace broken link to UX guide with new working link in the README.md
file.

cannonical -> canonical

This reverts commit 3e991230.

# Conflicts:
#	app/models/project.rb

[ci skip]

Closes #3649

[ci skip]

[ci skip]

Closes #2837

**Why is this needed?**
It just does look better in the Readme :-)

Signed-off-by: Jeroen van Baarsen <jeroenvanbaarsen@gmail.com>