Ability to override graph names and series labels

[jessereynolds]

The labels on data series captured by various systems are often not what you'd ideally display to consumers of the Visage graphs. Eg "if_octets-GigabitEthernet0_0_7 (rx)" may be more friendly renamed to "Level 3 Uplink Amsterdam" when creating the profile.

Similarly the name of the plugin / plugin instance that forms part of the graph label, eg "snmp on bdr01.ams.mybigisp.dom" could be renamed in the builder, eg to "Bandwidth (MB) on bdr01.ams.mybigisp.dom".

This could probably be implemented by creating aliases (display names) for each plugin, plugin instance, plugin instance type instance, and then have a custom constructor for the labels / graph titles, eg to optionally include each of the available variables (host, plugin, plugin alias, plugin instance, plugin instance alias, etc etc).