improving docblock for Set::extract and Set::classicExtract return types
Merge pull request #2967 from steinkel/feature/improve-set-docblock

improving docblock for Set::extract and Set::classicExtract return types
fixing Set docblocks
Merge pull request #2971 from steinkel/feature/improve-set-docblock

fixing Set docblocks
Documentation correction

TimeHelper::$niceFormat to CakeTime::$niceFormat
Merge pull request #2988 from kp2356/patch-1

Documentation correction
Sort route keys in reverse length order before replacing to prevent incorrect matching
Added a test case
Removed comparison method
Fixed key sorting
Use array_keys instead of array_flip
Test if keys are empty before sorting
Made it slightly neater
Fixed PHPCS error
#2994, unnecessary calls to Model::__isset(null)
Changed if statement to force Travis rebuild
Merge pull request #2995 from tharlinsmith/ticket-2994

#2994, unnecessary calls to Model::__isset(null)
Merge pull request #2991 from mikegibson/route_params

Fixed incorrect replacement of route elements beginning with same string
Only sort the keys once per request instead of on each match.

Sorting the keys property by value sorts keys with the same prefix for
free. This does change the order of the keys, but I don't think that is
actually a large issue as it is just a list.

Refs #2991
Allow sub-directories for Fixture folder

Allow sub-directories for Test/Fixture folder (for app. and plugin.)
The directory separator is '/'.
A file ``MyClassFixture.php` in the folder `Fixture/MyFolder` will be included like this :
`'app.MyFolder/my_class'`