Resize: now re-entrant using new buffer api

As said in title.

**EDIT**: Considering that tp7 is going to do rewrite, I might as well as doing rewrite too, and will be using this branch. So, for now, don't pull yet. Or pull 	e319ef2

**EDIT2**: Okay, should be ready to be pulled. Rewrite is going to be done later when MT stabilize more.