For this change I have made the FFDocumentSearch class inherit from NSDocument. This way, we can register it with the window controller and will get callbacks when the window is about to close, with the option to cancel closing of the window. This approach seems much simpler than the alternative, which would be to introduce our own callback/delegate system for window closing, or have the window controller know about saving files.
This is work in progress but I don’t think any functionality is missing compared to previous commit, although some functionality might be less polished, e.g. the action buttons don’t properly enable/disable and the height of the results list gets lost when hiding it.
Some of the stuff that has changed / improved:
* The find/replace text fields adjust their height to encompass the content (closes#94). Presently though the initial height of the ontrols is one line regardless of content (but they should adjust on first edit).
* You can use Save All (⌥⌘S) to save affected files after Replace All (closes#558).
* The key equivalents / actions available in the Find dialog is now easier to find via the action pop-up, which also has enables accessibility.
* Using Next (⌘G) or Previous (⇧⌘G) with search results will move selection up/down.
* Using Find All with ‘in’ set to ‘Selection’ will find and select all matches in the current document, which fixes#425, though it might be more desirable to show the results in the find dialog (like Find All does for a document or folder).
