Improve quick search behavior in OutlineView, TreeTable, and ListView

[eirikbakke]

Quick search is the little search bar that pops up when you start typing in various NetBeans explorer view components:

This PR unifies the search bar behavior in OutlineView, TreeTable, and ListView, with some adjustments and bug fixes. Mostly the search bar should work like a search bar in any other app, e.g. Chrome. Some common alternative keystrokes are handled for Find Next/Previous.

Details:

• For OutlineView and TreeTable, avoid changing the selection when pressing Escape. (TreeView already has the desired behavior.)
• Add F3 and Ctrl/Command+G as alternative keystrokes for next-match (and Shift variants for previous-match).
• Have QuickSearch select all when invoking Ctrl+F or alternative shortcuts while the search bar is already open.
• Make the ListView's quick search box look more modern, and consistent with that of OutlineView/TreeView. Use the magnifying glass icon instead of the text 'Search', and use a flat border style. Note that ListView has a "floating" search bar instead of one attached to the bottom of the box; I have not changed this.
  • 
• Add more alternative find-next/previous keystrokes for ListView, like I did in the QuickSearch class (which is used by TreeView and OutlineView but not ListView). On Ctrl+F or F3, open the search bar, or select-all the existing text if it is already open.
• In OutlineView and TreeTable, avoid backtracking to the first hit if backspace is pressed on a still-matching selection.

[mbien]

moving to NB29