Use AIFilePicker everywhere.

Also upgrade the file picker filters with the new extensions found
in the orginal file picker code of Singularity.

Also improve AIFilePicker a bit: added hasFilename() and now
deleting the statemachine automatically by default: it's no longer
needed to call deleteMe from the callback.

indra/newview/llpreviewnotecard.h

@@ -46,6 +46,7 @@
 class LLTextEditor;
 class LLViewerTextEditor;
 class LLButton;
+class AIFilePicker;
 
 class LLPreviewNotecard : public LLPreview
 {
@@ -128,6 +129,7 @@ protected:
 	// <edit>
 	virtual BOOL canSaveAs() const;
 	virtual void saveAs();
+	void saveAs_continued(AIFilePicker* filepicker);
 	// </edit>
 };