docs/git-clone: clarify use of --no-hardlinks option
docs/git-clone: clarify use of --no-hardlinks option

Current text claims optimization, implying the use of
hardlinks, when this option ratchets down the level of
efficiency. This change explains the difference made by
using this option, namely copying instead of hardlinking,
and why it may be useful.

Signed-off-by: Albert L. Lash, IV <a9a6b986e12b5362c13e04986b43188dff25e0c0@bloomberg.net>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git