* Did not touch archived walkers... those can be named whatever.
* Kept abstract classes that end in Walker untouched (e.g. LocusWalker, ReadWalker, ...)
* Renamed a few inner classes due to conflict when stripping off Walker from their outer classes: ContigStats, FlagStats and FastaStats.
Index expanded to use summary() annotation field
UserExceptions, ReadFilters, GATK engine all use the system to generate docs
Doclet expanded to handle lots of new cases