standardize/delocalize API 'timezone' response

[katanacrimson]

Would be more ideal to, instead of using a localized string, to use something like "-0500" for timezone data in a user's profile. We can localize that easily enough and work with it on our own - could also provide it as a string. This would make mathematical operations easier.

ex:

{
    "timezone":{
       "offset":"-0600",
       "humane":"Central Time (US & Canada)"
    }
}