Fixed unreliable file closing in set_contents_from_filename and get_contents_to_filename methods of boto.s3.key.Key
Fixed unreliable file descriptor closing, added file cleanup for get_contents_to_filename()
Merge branch 'vladimir-sol-develop' into develop

* vladimir-sol-develop:
  - Fixed unreliable file descriptor closing, added file cleanup for
  get_contents_to_filename()
  - Fixed unreliable file closing in set_contents_from_filename and
  get_contents_to_filename methods of boto.s3.key.Key

Conflicts:
	boto/s3/key.py