select_date: in memory timestamp should be UTC

[rdoursenaud]

This induced a subtle hour bug because the dol_print_date() on the following lines were expecting an UTC timestamp.

Please also merge to 3.4, 3.5 and develop (do not cherry_pick).

[eldy]

I pushed a better fix into 3.5
Yours is wrong because you suppose: in memory, timestamp should be UTC
This is what it should be. However, dolibarr was not designed with this rule (historical reason), and the rule that is currently running is: in memory, timestamp are according to PHP server timezone.

I clean code for each version to prepare to switch with correct rule, but before that i fixed the function to match the rule that is followed by all other functions.

[rdoursenaud]

Well, I didn't suppose, I red the wiki:
http://wiki.dolibarr.org/index.php/Language_and_development_rules#Dates_and_Timezones

If these aren't the current rules, this needs to be updated.

Anyway, without this fix, the time support I added to project tasks is broken and any automatic dol_print_date() for that matter.

Could you reference the commit where you added your better fix, please, so I can test? Just copy/paste the reference hash, GitHub does the rest.