#27 Add TABLE:sort option

[Wim Nelis]

This patch adds the option to sort the primary alias of a table on its value. By default the primary alias is sorted on the index part of the numerical OID of the primary alias. Some types of switches add the logical interfaces in the order of their definition to the MIB. The individual interfaces become easier to locate in the table when using the new sorting method.

Optionally two parameters can be passed with the TABLE:sort option, which are used to transform the value of the primary alias prior to sorting. The definition "TABLE:sort(RE_m;RE_s)" causes a "s/RE_m/RE_s/" to be evaluated.