[PATCH] Document 'max' option to --grow --size in --help output.

[NeilBrown]

Suggestion from Christian Hudon <chrish at debian.org>

Signed-off-by: NeilBrown <neilb at suse.de>
---
 ReadMe.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/ReadMe.c b/ReadMe.c
index 88c4433..3164322 100644
--- a/ReadMe.c
+++ b/ReadMe.c
@@ -517,7 +517,8 @@ char Help_grow[] =
 "  --layout=      -p   : For a FAULTY array, set/change the error mode.\n"
 "  --size=        -z   : Change the active size of devices in an array.\n"
 "                      : This is useful if all devices have been replaced\n"
-"                      : with larger devices.\n"
+"                      : with larger devices.   Value is in Kilobytes, or\n"
+"                      : the special word 'max' meaning 'as large as possible'.\n"
 "  --raid-devices= -n  : Change the number of active devices in an array.\n"
 "  --bitmap=      -b   : Add or remove a write-intent bitmap.\n"
 "  --backup-file= file : A file on a differt device to store data for a\n"
-- 
1.5.6.5