FIXED -- Added Serialization and Plugin support (v0.2.0):
- added serialization encoders and decoders for NmapReport
- added basic plugin capability to NmapReport
- added basic mongodb plugin to validate plugin setup

TODO:
- Add Sphinx DocStrings
- NmapParser should be able to be fully generic and return Objects
- NmapParser should not need a XML root
- Add new plugins to support import/export from mysql, couchdb, csv
- support iterators for NmapReport::scanned_hosts
- add support for parsing os version (fingerprint)
- add unittest for udp scans, ping sweeping
- add support for 'resume' capability (see nmap --resume)
- review thread management for NmapProcess