Add timezone support

[germanviscuso]

Not sure if this was actually merged: sameerkumar18/aztro#3
but if there's timezone support in Aztro already you should definitely support it in your library. Asking for info for yesterday, today and tomorrow has no meaning without passing a timezone as the api consumers are not necessarily on the same timezone as the server.

[inthernar]

Was TimeZone support added?
I tried adding the $tz parameter but it didn't work.
I looked in the white pages, they were not updated to include the TZ parameter.

I am currently trying to figure out a way to calculate the differential between the server time and device local time, then adjusting &day to be either today, tomorrow, yesterday...

Would be a lot nicer if this was done on the server lol. Thank you in advance :)