new feature: auto tabindex

Tabindex, in most cases, had incorrect index. Some forms had no
tabindex at  all. Now tabindex_auto.js append tabindex to all
elements by jquery selector ":input, a[name=submit], a.input".
MAC Address List format unification

deviceconfig.php:
        xos12ReadMacList now returns mac address in cisco like format
Merge branch 'maintenance-0.20.x' of github.com:RackTables/racktables into maintenance-0.20.x
Merge branch 'maintenance-0.20.x' of github.com:RackTables/racktables into maintenance-0.20.x

Conflicts:
	ChangeLog
Merge branch 'maintenance-0.20.x' of github.com:RackTables/racktables into maintenance-0.20.x
generateEntityAutoTags: clarify comment
getNiftySelect(): removed $tree argument