private method doesn't work for singleton methods defined this way
Add tests to ActiveSupport:XmlMini to_tag method
additional note about routes in functional tests for engines [ci skip]
Fix insertion of records for hmt association with scope, fix #3548
Auto-generate stable fixture UUIDs on PostgreSQL.
Fixes: #11524
Merge pull request #12016 from roderickvd/uuid_fixes

Auto-generate stable fixture UUIDs on PostgreSQL

Conflicts:
	activerecord/CHANGELOG.md
	activerecord/lib/active_record/fixtures.rb
	activerecord/test/cases/adapters/postgresql/uuid_test.rb
	activesupport/CHANGELOG.md
Improve Contributing to Rails Guide

Logically group the content, so it makes more sense if someone tries to read from start of page to end of page. [ci skip]
Add documentation for Thread#freeze
Keep debugger support only for rubies < 2.0.0
Update Gemfile templates to provide correct debugger
Update debugging guide to use byebug
Instead boat load of libraries, simply say StdLib
Make the reflections cache work with strings as its keys.
No need to call `to_sym` on reflection name, since the cache now works
with strings with string keys.

Related #14668.
Make the aggregate_reflections cache work with strings as its keys.
Make sure the reflection test is passing a String to the reflection
cache.
Merge pull request #14675 from laurocaetano/make_reflection_caches_works_with_string_keys

Make reflection and aggregate_reflection caches work with string keys.
Remove extra collect call
Only call uniq on the conditional that actually needs it
Merge pull request #11411 from dscataglini/master

Active support callback's before/after/around filters are not correctly making their singleton methods private