git-svn: enable delta transfers during fetches when using SVN:: libs
This should drastically reduce bandwidth used for network
transfers. This is not enabled for file:// repositories by
default because of the increased CPU usage and I/O needed.
GIT_SVN_DELTA_FETCH may be set to a true value to enable or
false (0) to disable delta transfers regardless of the
repository type.
Signed-off-by: Eric Wong <normalperson@yhbt.net> Signed-off-by: Junio C Hamano <junkio@cox.net>