Set language from browser, accept enter key in planner #242 #243

[Bertware]

Resolves issues #242 and #243.
Note:
\Locale::lookup is a php function from the php_intl module. The page won't show if this module is not available.

[Haroenv]

Looks great to me

[Haroenv]

Tests will need to change I guess.

[pietercolpaert]

Looks good indeed! Can you fix the test as well?

[pietercolpaert]

This probably means we can finally get rid of the cookies as well, right?

[Bertware]

While fixing the tests, I also added some new tests, to ensure that special cases are handled correctly. The language detection has been changed, instead of locale_lookup we're now using our own method. This was needed to support headers like "da, nl;q=0.9, en;q=0.2", where danish is not supported but Dutch and English are. While locale_lookup would fail, our own method will select nl in this case.

About the cookies: since users can still override the language, the cookies are still used. Otherwise, the override (?lang=) would have to be present in every url. Currently the cookie is set:

• if ?lang is available, use it as override and update cookie
• if cookie set and ?lang not set, use cookie
• if ?lang and cookie not set, use browser language and update cookie

If someone would block cookies however, he could still use the site based on the accept-language header. (instead of always returning to the language selection)

[Bertware]

Cookies will have to stay required. When using a device frome someone else with a different browser language, users should still be able to pick their language (looking up trains while at a friend, for example). However, maybe we can keep all cookie code in the language middleware, including the pick language redirect (this redirect is currently still located in the home controller).

Also note that cookies to remember a language are allowed in the updated cookie law. (since widely used for user expierience, and not used for tracking)