Hierarchical error messages plus some more tweaks

- hierarchical error messages for different error types
- renamed ofp_stats_types to ofp_stats_type
- renamed OFP_VENDOR to OFP_EXPERIMENTER in OF 1.0 input file
- use ofp_capabilities enum in of_features_reply
- use boolean type for l2_table_enable field in of_bsn_set_l2_table_(request|reply)
- return Set<OFActionType> for actions field in of_features_reply
- added DatapathId class that's returned for datapath_id field of of_features_reply
- removed unused read/write routines from OFBufferId
- added getOFVersioon method to factory classes/interfaces
- renamed OFPT_MULTIPART_(REQUEST|REPLY) to OFPT_STATS_(REQUEST|REPLY) in OF 1.3 input file
- renamed ofp_multipart_types to ofp_stats_type in OF 1.3 input file
- tweaked python backend to work with consistent use of of_stats_xyz vs. of_multipart_xyz in 1.3
Merge branch 'master' of github.com:floodlight/loxigen
Add extensions for LLDP PDU offload on switches
Fix issues with C backend with new error message hierarchy
Test two different error types in error message unit tests

- Added coverage for C and Java backends to the error msg tests
Fixed bug in C versions of error message unit tests
create wireshark backend
wireshark: basic message parsing
wireshark: generate enums
wireshark: stub dissectors
wireshark: ignore tenjin cache files
wireshark: add OFReader class

Based on the pyloxi implementation.
wireshark: begin defining dissector fields in python
wireshark: use correct subtree
wireshark: begin generating fields from IR
wireshark: add port 6653
wireshark: add copyright to output file

This must be GPLv2 because it uses Wireshark APIs.

http://ask.wireshark.org/questions/1059/license-of-dissectors-written-in-lua
wireshark: add license to templates
openflow_input: add discriminator to of_table_feature_prop
ir: add discriminator method to OFClass

Also fixed the broken member_by_name.