refs #1234: Added readable_list() method to Text class.

This method takes an array of strings and converts them into a human readable list. For example: array('eggs', 'milk', 'cheese') => "eggs, milk and cheese".
refs #4626: Added readable_list() method to Text class.
Moved the conjunction property into a parameter of readable_list().
Merge.
- Fixed brace position to comply with style guide.
- Improved exception message.
- Added parameter for the use of serial commas.
- Made serial comma parameter default to TRUE.
- Optimisation to remove unrequired loop.
- "Validation" exceptions changed to: InvalidArgumentException.
Added support for objects that implement __toString().
Re-factored string building.
Formatting and comment improvements.
Merge pull request #328 from marklocker/3.4/feature/4626-readable-list-method

refs #4626: Added readable_list() method to Text class.
Merge branch '3.3/develop' into 3.4/develop

Conflicts:
	classes/Kohana/Text.php
Improved examples in DocBlock.
Merge pull request #380 from marklocker/patch-1

Improved examples in DocBlock. (refs #4626)
redo of PR: Added Arr::count() helper (refs #4516)
Merge pull request #386 from melvinmt/bugfix/4516

redo of PR: Added Arr::count() helper (refs #4516)
Add $mode to Arr:count() method (refs #4516)
Refs #3916: Deprecating windowed_urls
Changed the tag to 3.4.0
Refs #4178: Use different approach for MB and MiB
Added documentation to the function