This adds a concise description of a tool to its usage text.
A first form of this patch was proposed by Steven Honeyman
(see http://www.spinics.net/lists/util-linux-ng/msg09994.html).
Signed-off-by: Benno Schulenberg <bensberg@justemail.net>
* multipurpose binaries (symlinks) suck when used with autotools
* swapoff shares small subset of the code with swapon
* usage() and 'struct option' is unnecessary complex when shared
* shorter and simple code is easer to maintain...
Signed-off-by: Karel Zak <kzak@redhat.com>