In Router::_parseString(), adding . (dot) to the regex character class, for matching library-based routes specified in "compact syntax," e.g., 'myplugin.Posts::index'

Prior to this update, library dot notation did not work when using compact URL syntax. For example,

$url = Router::match(array('myplugin.Posts::view', 'id' => '1138'));

failed because the . character within the controller component ('myplugin.Posts') is unrecognized by _parseString(). By including the . character in the regex pattern, the above compact URL path will not fail, and the controller portion, "myplugin.Posts" will subsequently be parsed by _parseController(), which recognizes the library dot notation.