svn-fe manual: Clarify warning about deltas in dump files
svn-fe manual: Clarify warning about deltas in dump files

Those in the know would notice that dump file format version 2
means "svnadmin dump --no-deltas", but for the rest of us, an
explicit reminder is useful.

Signed-off-by: Jonathan Nieder <b57189c5f2fd5b3daf3350a77fde90def1080fa5@gmail.com>
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