MFC r207094 (by marcel):

MFC r207094 (by marcel):
Implement the resize verb and add support for resizing partitions
for all schemes but EBR.

MFC r207095 (by marcel):
Implement the resize command for resizing partitions. Without new
size, the partition in question is resized to fill all available
space.

Approved by:	kib (mentor)

git-svn-id: svn://svn.freebsd.org/base/stable/8@209497 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f