Merge pull request #1981 from abhibeckert/master

Resolve #1974:  Allow un-mapping of Ctrl-H
Add project specific setting to use tabs for indentation
Merge branch 'master' of https://github.com/sequelpro/sequelpro
Add pref to disable backticks in completions

Add a checkbox to the Editor preferences to disable placing backticks
around attributes when completing in the custom query pane.

Resolves #764