Merge branch 'master' into handle-categories-in-site-config-defaults
Set categor[y|ies] on post if they appear in site frontmatter defaults
Add collections to info about pagination support.

Currently: _Pagination does not support tags or categories_
Proposed: _Pagination does not support tags, categories or collections_

Maybe in the future? Related: #2376
Adding to pagination note: Cannot include collections

Adding a sentence to the paragraph to clarify, that pagination is restricted to posts and that it can't contain collections.
Allow subdirectories in _data
Add _data sub-folder support to docs
Add scenario for ensuring data folder over file precedence
Override collection url template
Encode URLs in utf-8 when escaping and unescaping

There is a problem while returning a path that has some special and possible Non-ASCII characters that may lead jekyll to break while doing the unescaping process. This is can be addressed by “forcing” ASCII to UTF-8.
Prevent table from extending parent width

The table containing the _Permalink style examples_ [in the docs](http://jekyllrb.com/docs/permalinks/#permalink-style-examples) extends the width of the content container.

The solution I propose is a bit dirty, because I remove `permalink: ` in the left column to make the table fit.

Another way would be using `white-space: normal;` for code inside tables. That would lead to _ugly_ line-breaks within the code.

What do you think?
Add tests to validate encoding of URLs

Added tests to validate the encoding of returned URL strings
after been escaped or unescaped.
Force encoding before escaping or unescaping

This will reassure not having any errors when escaping or
unescaping.
Change test to make it pass in Ruby 1.9.3
Revert changes and add encoding to the test file

* Add encoding to the test file as Ruby 1.9.3 doesn’t defaults to utf-8.
* Remove the forced encoding as encode seems too aggressive.
Prevent code overflowing container
Remove extra period. [ci skip]
Merge pull request #2429 from jshawl/code-overflow-fix
Update history to reflect merge of #2429 [ci skip]
Merge pull request #2430 from ivantsepp/doc_fix

Extra period in collections documentation
Update `Utils#pluralized_array_from_hash` and `Utils#value_from_singular_key` per suggestion from @parkr

Switched to using the `#tap` method for more concise code. Also returning the value from
`value_from_singular_key` instead of returning an array wrapped presentation of the value.
This allows for a one-liner in `pluralized_array_from_hash`.