Fix some missing ViAppController casts.
Fix deprecated compositeToPoint: usage.
Add missing delegate protocol to ViAppController.
Fix delegate declaration in ViBufferedStream.
Fix ViTextStorage references.

Because NSTextView’s textStorage is now a property, we
can’t override the accessor with one of return type
ViTextStorage * without triggering a compiler warning.
Instead, we provide viTextStorage, which provides access to
the appropriate type, and call that when we need a true
ViTextStorage instance.
Project tweaks.

Update various settings.
Update sparkle commit.