VOL-4964 - Update the core contributors list.

overview/contributing.rst
-------------------------
  o Removed some, added some

Change-Id: I50544101c9ca8f10bb5e2ccddba57437ae3d20ad
diff --git a/overview/lab_setup.rst b/overview/lab_setup.rst
index 47e8921..177143e 100644
--- a/overview/lab_setup.rst
+++ b/overview/lab_setup.rst
@@ -182,10 +182,10 @@
 
 To setup a NAT router on an Ubuntu 16.04 server you can look at this
 tutorial:
-http://nairabytes.net/linux/how-to-set-up-a-nat-router-on-ubuntu-server-16-04
+http :// nairabytes.net/linux/how-to-set-up-a-nat-router-on-ubuntu-server-16-04
 
 To install a DHCP server you can follow this tutorial:
-http://nairabytes.net/linux/how-to-install-a-dhcp-server-in-ubuntu-server-16-04
+http :// nairabytes.net/linux/how-to-install-a-dhcp-server-in-ubuntu-server-16-04
 
 Once the ``DHCP`` server is installed, you need to configure it.