Allow configuring HTTP connect timeout

[mephi42]

What does this PR do?

Allows configuring HTTP connection timeout for Tornado back-end.

What issues does this PR fix or reference?

None

Previous Behavior

HTTP connection timeout was always Tornado's default of 20 seconds.

New Behavior

If not explicitly configured, HTTP connection timeout remains 20 seconds. Otherwise user-specified value is used.

Tests written?

No

Commits signed with GPG?

Yes

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[DmitryKuzmenko]

LGTM

[rallytime]

I have one small request, and then I would also love to see docs added to the config docs.

[rallytime]

Can you move this to the bottom of the kwargs list? We don't want to cause an API change for people or other Salt functions using query who might be calling this with args/kwargs in a certain order.

[mephi42]

This is the call to fetch() - http://www.tornadoweb.org/en/stable/httpclient.html#tornado.httpclient.HTTPRequest (you need to expand the minimized lines to see this, otherwise this looks like query() parameter list), and there connect_timeout comes before request_timeout.

[rallytime]

Oh! You're right. My apologies.

[mephi42]

Added the docs for the new parameter and also for the existing http_request_timeout. I wasn't sure into which section to put them, so I created a new one.

[rallytime]

I like the new section in the docs - That looks good! I think adding this to the minion config docs would also be good.

[rallytime]

This should be Fluorine for the develop branch.

[mephi42]

Done

[mephi42]

In minion docs the related proxy_* are in "Minion Primary Configuration", so I put the new items there as well. For that reason I also moved them to "Primary Master Configuration" in master docs.