set timezone automatically

[terrazoon]

Description

Set the timezone automatically for the user based on what the browser says the timezone is.

We were using US/Eastern and 7 or 8 similar timezones to represent the US, but it turns out these are "legacy" timezones and the correct forward-leaning timezones all look like "America/Los_Angeles". These work fine for scheduling jobs and so forth, but just look a little different.

Since are going to be setting the timezone automatically, the user will not have the option to set their timezone to something else, so I suppose we need to remove the Change Timezone feature on the User Profile.

TODO (optional)

• TODO The setTimezone.js script is in the js folder instead of the javascripts folder because I didn't want it to disappear into all.js and get invoked everywhere all the time. Is that acceptable or what is the alternative?
• TODO After the timezone is set in the cookie, we need to invoke the python side of things, and I have just made a random call to the set_timezone() method from another function in the dashboard. This works and doesn't break any tests but is a bit inelegant.
• TODO Should we remove the Change Timezone feature on the User Profile? They can change it but it will get changed right back the next time the dashboard reloads.

Security Considerations

N/A

[jonathanbobel]

LGTM

[heyitsmebev]

Hey Ken, I left a couple of comments related to the js scripts placement

[heyitsmebev]

LGTM!