Display most representative country in timezone selector

[ancorgs]

Problems

Problem 1.

In the timezone selector the countries are only displayed if they are part of the name of the timezone (eg. America/Argentina/Buenos_Aires). In most cases, the name of the timezone includes only the global region and a concrete city (eg. Europe/Madrid). That makes hard to find the right timezone since the most intuitive mechanism (typing the name of the user country in the search box) is usually useless.

Problem 2.

There are some duplicated or controversial timezones that are not associated to any country. For more details this gist.

Solution

Add the "most representative country" to each timezone and display that in the UI. That information is read from the file /usr/share/zoneinfo/zone.tab.

That makes it easier to find timezones.

Timezones without a country (except those that really make sense) are filtered out. That removes controversy and duplicates.

Works even for the two timezones that have a different identifier at langtable and at zone.tab. Again, see the previously mentioned gist.

Testing

• Added new unit tests
• Tested manually (as shown in the screenshots)

[coveralls]

coverage: 74.758% (-0.002%) from 74.76%
when pulling a1d0c0d on timezone_small_fixes
into f55671d on master.

[imobachgs]

The code LGTM. But, please, update the changes files.

[joseivanlopez]

Maybe it is a matter of taste, but using one more column makes the selector to look a bit crowded. What about showing all parts in the first column and country in the second?

Africa - Ceuta                 Spain              10:10
Atlantic Ocean - Canary        Spain              09:10  

Timezones without country would have an empty second column, but that cases are only some exceptions.

[ancorgs]

What about showing all parts in the first column and country in the second?

I have no strong preference. So let's see.

This is how it looks now in this PR (keeping what existed and just adding a column for the country):

And this is how it would look what you suggest (merge the parts in to the first column and use the second for the country):

@dgdavid, @imobachgs, @joseivanlopez What do you prefer?

[imobachgs]

@dgdavid, @imobachgs, @joseivanlopez What do you prefer?

I would choose the second option as it is more clear to me: the localized name of the timezone and the country. If I see more columns, I need to somehow think what they are all about.

Having said that, I do not see the reason to use a hyphen to separate the components, but let's keep that for a different discussion.

[ancorgs]

If I see more columns, I need to somehow think what they are all about.

Good argument. Let's go for the second option then. I just added a commit to change that (although I don't think I will update the screenshots in the description).