clone,fetch: explain the shallow-clone option a little more clearly

"deepen by excluding" does not make sense because excluding a revision
does not deepen a repository; it makes the repository more shallow.

Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/clone.c

@@ -99,7 +99,7 @@ static struct option builtin_clone_options[] = {
 	OPT_STRING(0, "shallow-since", &option_since, N_("time"),
 		    N_("create a shallow clone since a specific time")),
 	OPT_STRING_LIST(0, "shallow-exclude", &option_not, N_("revision"),
-			N_("deepen history of shallow clone by excluding rev")),
+			N_("deepen history of shallow clone, excluding rev")),
 	OPT_BOOL(0, "single-branch", &option_single_branch,
 		    N_("clone only one branch, HEAD or --branch")),
 	OPT_BOOL(0, "shallow-submodules", &option_shallow_submodules,

builtin/fetch.c

@@ -122,7 +122,7 @@ static struct option builtin_fetch_options[] = {
 	OPT_STRING(0, "shallow-since", &deepen_since, N_("time"),
 		   N_("deepen history of shallow repository based on time")),
 	OPT_STRING_LIST(0, "shallow-exclude", &deepen_not, N_("revision"),
-			N_("deepen history of shallow clone by excluding rev")),
+			N_("deepen history of shallow clone, excluding rev")),
 	OPT_INTEGER(0, "deepen", &deepen_relative,
 		    N_("deepen history of shallow clone")),
 	{ OPTION_SET_INT, 0, "unshallow", &unshallow, NULL,