Fixed typos
Merge pull request #4146 from pborreli/typos

Fixed typos
Fix some comments.
Added a default response for all OPTIONS request that don't match a route.

OPTIONS requests that have routes matching other verbs should never
404. They should always return a 200 with the allowed methods in the
headers.
Added missing php version constraints
Updated the return values (comments/docs) of a couple of methods.
Fixed various typos and some additional phpdoc.