[epic] Implement full internationalization support for elections

[offbyone]

"Elections" in Wellington consist of two phases: Nominations and Voting. In all of those cases, the text displayed to the user is currently fully in english, and is calibrated on a per-convention basis.

To support i18n we would need:

• election model support for >1 language
• category model support for >1 language
• provide convention-specific text in a format compatible with i18n
• revamp the current text bundle model to be more friendly to i18n

... and that's just to start.