Clarifying behavior of 'unique' option in HABTM
cake -> CakePHP
Editing residue, bleh.  Thanks ADmad.
Improve Model::updateAll() documentation

Refs cakephp/cakephp#3729

Actual method signature is
@param mixed $conditions Conditions to match, true for all records
updateAll($fields, $conditions = true)
Merge pull request #1427 from majna/patch-5

Improve Model::updateAll() documentation
Merge pull request #1425 from cincodenada/master

Clarifying behavior of 'unique' option in HABTM