Improve map locale sorting / suggestion

[hholzgra]

Currently the map language list is sorted by two letter ISO country code, but has most prominently presents (mostly) local country names, so e.g. having Österreich (AT - Austria) mixed in between Argentina (AR) and Australia (AU).

Possible solutions:

1. present localized country names according to current UI language, and sort accordingly - that would require showing the language along with the country more prominently though for multi-lingual countries

2. present language list like in UI navbar instead of country list

The second approach would have the advantage that the list would be shorter, and that the user interface as a whole would be more consistent, but the flag icons might be controversial ... but then again they already are in the navbar anyway. The second approach would also reduce the amount of code as it could mostly be shared between both selectors.

Both approaches still have the problem that we only get the language code for the center of map, and have to decide which language to use by default for multi lingual countries. Preferably we should rather be able to have a reverse geocoder that provides us with the prominent language by region, but that would yet be another feature to add.

So a third alternative might be to have a three part form element, consisting of three or more radio inputs to choose from:

• current UI language
• "main" country language
• optionally: other local languages (official first, followed by unofficial / regional)
• "other" which would be a combination of a radio button and a select box

By presenting all local languages making one the "main" language would be less of an issue with the others also presented, and it would also make picking the "correct" language more easy as in most cases picking from the long list would not even be needed.

(See also prior #105 and #106)

[hholzgra]

Rough sketch of how a better language selection UI may look like