More UI test fixes

* Catch and ignore `InterfaceError` when a connection we're trying to kill is already closed
* `test_valid_login` waits for login button to be visible
Merge pull request #1315 from RickMohr/mohr-ui-test-fixes

Mohr UI test fixes
Return the same JSON for photo upload as plot info
Merge pull request #1317 from maurizi/fix-tree-photo-response

Return the same JSON for photo upload as plot info
Factor out datepicker init
Fix lint
Invert conditional order to make fn more readable
Don't keep a copy of elems, always recalculate

Elems is a pairing of dom elements to search clauses. For (upcoming) stewardship searches, the key and predicate change dynamically to contain model information based on the model the user selects in the dropdown. It will be required to recalculate this on every search.
Add support for udf collection searches

Make applySearchToDom called through searchBar so that it can in turn call the downstream method on a udfcSearch instance. This is required so that search.js doesn't have to init() udfcSearch, or import it at all.

Make a helper template tag.
Style udfc bar, select boxes, etc
Small changes to stewardship search styling, naming
Fix alignment issue with subheader, fix styling
Rename plot to planting site in udfc search