This also resulted in a refactoring of the Providers and parsing
Exceptions. NumberFormatException and ParseException can now be thrown
directly, the wrapping in a SmackParsingException is down at a higher
layer, i.e. in AbstractProvider.
notably add a cache for the active and default privacy list to avoid
IQ get/response round-trips.
Also add a few methods to PrivacyListManager to get the privacy list
names. The already existing methods always returned the whole list
together with the name, which caused two round-trips.
Simplified some code.
Properly escape Privacy XML.
Florian Schmaus