private method doesn't work for singleton methods defined this way
Add tests to ActiveSupport:XmlMini to_tag method
The `source` option for `has_many => through` should accept String
values.

With the changes introduced by 16b70fddd4dc7e7fb7be108add88bae6e3c2509b
it was expecting the value to be a Symbol, while it could be also a
String value.
Merge pull request #14668 from laurocaetano/source_option_with_string_value

The :source option for has_many => through should accept String values.
add services: memcache to travis
Merge pull request #14671 from arthurnn/travis_memcache

add services: memcache to travis
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
+EOL
Correct factual error for page not found
Merge pull request #14679 from pbharadiya/master

Correct factual error for page not found [ci skip]
[ci skip] Update code snippets to latest master (initialization.md).
Also update the `server.run` example (Replace Mongrel with Puma).
Merge pull request #14677 from JuanitoFatas/update-initialization-code-snippets

[ci skip] Update code snippets to latest master (initialization.md).
Merge pull request #11656 from emre-basala/xml_mini_test

Add tests to ActiveSupport:XmlMini to_tag method