Added query editor tool.

# Query Editor (Proposal)

An alternative/supplemental tool to the OOTB QueryBuilder Debugger at `/libs/cq/search/content/querydebug.html`. Provides a quicker workflow for authoring query descriptions and previewing results. However, some functionality such as the XPath query translation, filtering predicates list, query tree notation, ATOM feed link are not available.

## Features

- Query results are automatically reloaded as the query description is edited.
- Autocomplete available (ctrl+space) for the following:
  - query description predicates - at the start of a line.
  - crx paths - after a `path` predicate.
  - node types - after a `type` predicate.
- Navigate to resources in CRXDE Lite from the results panel by holding the meta key (command key on macs, windows key on pc) and clicking the path.
- Comment lines starting with `#`.
- Common code editor features such as syntax highlighting, code folding (for JSON objects in the query results).