Expose -getInstance:withArgArray: in the BSInjector protocol
Expose -getInstance:withArgArray: in the BSInjector protocol

* Also add appledoc to the protocol methods, including indicating that
  the other -getInstance* methods are convenience methods
jbsf/blindside,jbsf/blindside,jbsf/blindside,lumoslabs/blindside,lumoslabs/blindside,lumoslabs/blindside