#861: Merging DNP3 Analyzer

HI, Robin,

Can you please take a look at current version of the codes. I added documentation on the analyzer.

The work that left undone so far is
(1) so far, we support logic DNP3 application layer fragment as long as 65536.
(2) documentation on protocol validation policy, the policy that checks some rules defined by DNP3 protocols


Hui Lin