Fix hestiacp#104. Default dkim size is now set to 1024

Author: serghey-rodin

bin/v-add-mail-domain

@@ -18,7 +18,7 @@ domain_idn=$(idn -t --quiet -a "$domain")
 antispam=${3-yes}
 antivirus=${4-yes}
 dkim=${5-yes}
-dkim_size=${6-512}
+dkim_size=${6-1024}
 
 # Includes
 source $VESTA/func/main.sh