Add ability to set timezone in PHP

[paalbra]

I haven't seen this mentioned in any issues, but it is something I would like to see added myself.

It adds an ability to set time timezone directly in PHP.

If this is used you won't need to override the timezone in MISP itself. I.e. here: https://github.com/MISP/MISP/blob/7283c8183ac5144f3cbc6f415dd6b1329a4435fa/app/Config/core.default.php#L243-L247

I've tried to follow the same coding style like I've seen in other scripts. Happy to hear any comments/thoughts.

[paalbra]

@coolacid Do you have any thoughts regarding this? :)

[paalbra]

I've fixed this in my own MISP, but I just realized that this PR actually was missing the part that sets timezone for cli. Added one new commit.