Rename FileViewModel to QuerypointViewModel for issue #140

Recreate FileViewModel as container for QuerypointViewModel and EditorViewModel

Move FileViewModel ctors to FileViewModel class.
Use ko if operation to block showing QPOutput for eg html
Rework editor resizing to support multiple editor views
Trial UI: resetChain() to most recent query when it activates
Any ko subscriptions need dispose() calls, ugh
Delay the editor sizing to avoid N+1; reorder chain
Remove extra logging
Add new debug option useAsyncPreprocessor
Fixes #141, jQuery extend fails, i-- transformed incorrectly,
use === not = to test condition ;-)