Using these two values ties requests to a
particular query position within a panel, ensuring
that requests are canceled if:

- Duplicate requests with the same query are sent
- Requests from the same query position (but a
different query) are sent

The last point is important as it identifies
queries by a physical location in the dashboard
instead of with the query expression.  If a
different query from the same position in a panel
is sent, the previous request should be canceled.

Insert missing backtick.

* added hex units

* deleted blank line, to fix style error

* added unit tests

* updated unit tests and changed the way it handles negative hex0x

fix(login): fixed so that you  get redirect back to the page or dashboard you where on when you clicked on sign in link, fixes #3312

feat(templating): refactoring template variable handling for variables that change on time refresh, closes #5021