browser: Added SNMPv3 AES encryption (issue #24)

build: Renamed Ant build files for clarity

browser: Added MibTypeSymbols to the MIB tree

Updated version history for version 2.9.4.

Updated list of future enhancements in documentation.

Fixed omitted character in extract from error MIBs (bug #26150).

Fixed issue with file streams not closed properly on parse errors (br…

…anch 2.9, bug #26082).

Branched for the release of version 2.9.

Release branching of version 2.8.

Updated ASN.1 grammar version number and copyright date.