Add list of defined keywords to the View (and Report) Filter Editor dialog

Javatest 4.2.1

- Start Harness
- Change "View Filter" to "Custom" and open "Edit Filter" dialog.
- Select "Keywords" tab.

This tab prompts user to write keyword name instead of allowing him to select from list (like in Configure/Quick Set mode).

Keyword input controls should be consistent within the harness. Filter Editor dialog should show allowed keywords to select from.

Same applies to the "Custom" filter used in Create Report dialog.