Workbench autocomplete should be smater

[JRobTS]

Description

The Druid Console Workbench will auto-complete in the wrong contexts and should be smarter.

I propose the following changes:

• "enter" shouldn't trigger an auto-complete
• Numerals should not be candidate for autocompletion
• Inside of double quote "" blocks, function names should not be candidate for autocompletion: datasource and field names only
• Inside of single quote '' blocks, should not be candidate for autocompletion
• Other common / completed phrases such as NULL and "count" should not be candidate for autocompletion

Motivation

Make working with Workbench less annoying.

For example, "1" will auto-complete as "LOG10" on (enter). This is extremely annoying as it's pretty typical to write a query that ends in GROUP BY 1; only to have auto-complete change it to GROUP BY LOG10.

Other annoyances include when writing inside of a string block ("" or '') the auto-completer will try to fill in function names. AND subject = 'foo' will auto-complete to AND subject = 'FLOOR'

Datasource and field names should be within context for double quotes "", but not function names. And I can't think of any reason to auto-complete when inside of single quotes '' (maybe local context)

More examples of auto-complete annoyances:

• IS NOT NULL auto-completes to IS NOT NULLIF
• SUM("count") auto-completes to SUM("COUNT")