Let create_scalar_function take an FnMut instead of a extern "C" fn.
Let create_scalar_function take an FnMut instead of a extern "C" fn.

mikelodder7/rusqlcipher,xinghun92/rusqlite,mikelodder7/rusqlcipher,jgallagher/rusqlite,gwenn/rusqlite,gwenn/rusqlite,jgallagher/rusqlite,xinghun92/rusqlite,jgallagher/rusqlite,mikelodder7/rusqlcipher,xinghun92/rusqlite,gwenn/rusqlite