Add "Add new DNS server" button

Added a button which allows the user to add new DNS Servers.
After pressing the button a new empty field appears.

Resolves openbmc/openbmc#3089

Tested: Added several new DNS Servers on a Witherspoon.
Change-Id: Ic6a6d2b798ad177b0e9aeb64ba3e4993af442305
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/app/configuration/controllers/network-controller.html b/app/configuration/controllers/network-controller.html
index dc81ed3..f6d0a5d 100644
--- a/app/configuration/controllers/network-controller.html
+++ b/app/configuration/controllers/network-controller.html
@@ -80,6 +80,7 @@
 							<label for="net-config__prime-dns">DNS Server {{$index+1}}</label>
 							<input id="net-config__prime-dns" type="text" ng-model="dns" ng-blur="interface.Nameservers[$index] = dns"/>
 						</fieldset>
+						<button type="button" class="btn-primary inline" ng-click="interface.Nameservers.push('');">Add new DNS server</button>
 				</div>
 			</fieldset>
 			<div class="network-config__submit-wrapper">