Bug 35498: Allow tab to indent lines and trigger autocomplete

Bug 35498: Allow tab to indent lines and trigger autocomplete

This patch allows the tab key to indent lines as well as trigger autocomplete.

Test plan:
1) Apply patch, navigate to reports and create a new SQL report
2) Click in the text editor and press tab, it should indent and then trigger the autocomplete options
3) Type something to select from the autocomplete box and press tab - it should autocomplete that option
4) Type any word and then press space. Now press tab and it should indent again

Signed-off-by: Andrew Fuerste-Henry <andrewfh@dubcolib.org>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>