[IM] don't die if the switch FDB cannot be read
[IM] don't die if a switch is unreadable.  complain loudly instead.k
[IM] Update bundled OUI file
[HK] Pre V3 OUI / SEC stuff that is no longer valid
[DB] New table to store OUI organisation details. For issue #87
[NF] OUI utility class to download and parse the IEEE OUI data file - for issue #87
[NF] Update OUI database from named file or IEEE website - for issue #87

Typically called as:

    bin/ixptool.php -a oui-cli.update-database

which will create / update the OUI database directly from the latest IEEE file from their website.

A specific file can be passed via the `fromfile` parameter. You can also force a
database reset (drop all OUI entries and re-populate) via the `refresh` parameter.

Neither of these options are typically necessary:

    bin/ixptool.php -a oui-cli.update-database -p fromfile=/path/to/oui.txt,refresh=1

Note that we bundle a recent OUI file in `date/oui` also.
[HK] Documentation
[NF] Show manufacturer of an OUI in the MAC address table listing. Closes #87
Merge branch 'nf-mac-octet'
Merge branch 'master' of https://github.com/inex/IXP-Manager
Version bump