Update README to reflect Manager functionality

slapos/README.format.txt

-format
+Format
 ======
 
 slapformat is an application to prepare SlapOS-ready node to be used inside SlapGrid Cloud.
@@ -10,6 +10,7 @@ It "formats" the machine by:
  - creating needed tap interfaces
  - creating TUN interfaces
  - creating needed directories with proper ownership and permissions
+ - (optional-manager) creating cgroup resource tree for slapos
 
 It reads configuration from /etc/opt/slapos/slapos.cfg and formats computer
 accordingly. The variables are number of partitions, IP addresses, storages
@@ -22,6 +23,9 @@ partition ~/.slapos-resource. This file contains network interfaces,
 IP address ranges and port ranges. The resource constraints can be 
 recursively folded. 
 
+Pluggable parts for formatting are available too. They are called Managers
+and can be turned on/off via configuration property manager_list.
+
 This program shall be only run by root.
 
 Requirements
@@ -34,5 +38,4 @@ Binaries:
  * brctl
  * groupadd
  * ip
- * tunctl
  * useradd