documentation correction
Merge branch 'master' into dev
Add request seletor for $_REQUEST array
Add the ability to process multiple fallbacks

See [this
discussion](http://forums.modx.com/thread/86543/help-with-previous-next-
navigation#dis-post-477230) for a use case.
Add parents and parentsi selectors
Add UparentB and parentB selectors
v 2.2.0-pl
Merge branch 'dev'