First steps to localisation

Created a hueg resource file that contains pretty much all of the strings that should benefit from localisation.

- [x] Replace exception messages with strings from the resources.
- [x] Update tests where relevent.
- [x] Replace help message descriptions with resource-based versions.
- [x] Update templates to use resource-based strings.
- [x] Dump localisation object containing strings used by javascript in bottom of main index template.
- [x] Make javascript actually use these.
- [x] Make messages more consistent in terms of punctuation, tense, wording.
- [x] Remove no-longer-relevant references to nick or nickname (now "user"), update command info to capture current system (stuff like notes aren't shown with a paper-clip anymore)
- [x] Bring Nancy culture to the thread.
- [x] Make Nancy specify UTF-8.
- [x] Make sure everything is bulletproof. (Partially done).
- [x] RFC on changes in general.
- [x] Figure out if it's worth (or possible to) allow in-client localisation or having a separate app for localisation.  (nah, it's not worth either at this stage if it's going to take me another week to get around to looking at it).
- [ ] Add a user option to allow overriding the language sent by the browser.

There may be a couple of rough edges and things that can benefit from being refactored, but all of the major pieces should be there and done.