Remove clientAuth from signed certificates by default

Signed-off-by: KheOps <kheops@ceops.eu>
Remove nonRepudiation key usage from signed certificates by default

Signed-off-by: KheOps <kheops@ceops.eu>
Add default_bits set to 4096 for the request creation config file

Signed-off-by: KheOps <kheops@ceops.eu>
Add little more explanation on 'pathlen:0' specification for the root CA

Signed-off-by: KheOps <kheops@ceops.eu>
Improve explanation on root CA key usage

Signed-off-by: KheOps <kheops@ceops.eu>