These changes are mostly related to restructuring the regular
expression patterns to make them more readable by defining constants. 

The other changes included are:

- support  the "targattrfilters" target keyword
- make the "search" right behave correctly
- fix a bug in the way we evaluate multiple permission bind rule pairs 
- the targetattr wild-card "*" will now not return operational
  attributes; operational attributes now need to be explicitly defined
  in the targetattr rule to grant access