Documentation updates for PSDK error code improvements

Adding errorInfo attribute to support underlying error code improvements outlined here:
http://wikis.rim.net/display/bbaw/PSDK+Error+Code+Improvements

@bryanhiggins identified that this may not be the correct place to put docs changes anymore, but ensured they would get to the correct place. 

NOTE: this depends on 10.2 OS, so some form of minimum version control is required. This has also been discussed with @bryanhiggins.