cvsimport: Improve documentation of CVSROOT and CVS module determination
cvsimport: Improve documentation of CVSROOT and CVS module determination

Document the fact that git-cvsimport tries to find out CVSROOT from
CVS/Root and $ENV{CVSROOT} and CVS_module from CVS/Repository.

Also use ` ` syntax for all filenames for consistency.

Signed-off-by: Frank Lichtenheld <86a8c2da8527a1c6978bdca6d7986fe14ae147fe@lichtenheld.de>
Signed-off-by: Junio C Hamano <dc50d1021234060e53ec42a77d526afa2fe07479@cox.net>

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