Fix: Cancel link click if triggered as part of text selection

Prevent a click if the user select content in a topic and release the mouse over a link.

https://meta.discourse.org/t/selecting-a-link-results-in-it-being-opened/14846
show parent and child category in oneboxes
UX: Move emoji setting into 'Plugins' category
FIX: Support ember app routing to topics with only slugs
SECURITY: Stripping links could unescape html fragments
Revert "FEATURE: fenced code blocks can hint with "pre" or "text""

This reverts commit 943ad8d1d54cc39f297198c338d484d98a4e7536.
FIX: When emoji was disabled you could get a JS error in preview
FIX: update user preferences was failing if custom_fields is blank string
Revert "Revert "FEATURE: fenced code blocks can hint with "pre" or "text"""

This reverts commit 4487d6a4c25ba5d3a366e2a8ada489a6a08d67ab.
correct tests
SECURITY: rate limit change email requests
Merge pull request #2804 from lidel/plugins-category-in-settings

UX: Move emoji setting into 'Plugins' category
FIX: double-escaped single quotes in URLs
FIX: missing avatar when sizing down window
FEATURE: advanced category:NAME search operator
FIX: word-wrap missing from search
FIX: link to sub category not working in search
UX: gutter links use link color, no glyphs
UX: change "foo said:" to "foo:" in quotes
adjust track-link alignment in gutter