Use HTTP to download kernel and initital RAM disk

As of version 3.70 (Fuel uses 4.02) pxelinux can download files
via HTTP.

DHCP option 210 sets prefix for all files that pxelinux downloads.

Doc-Impact: ops-guide
Closes-Bug: 1521759

Change-Id: Idb7dfde333a0b533699ebb976d94d03b5ede295a

deployment/puppet/cobbler/manifests/server.pp

@@ -199,6 +199,15 @@ class cobbler::server (
     notify  => Service[$cobbler_web_service],
   }
 
+  file { '/etc/httpd/conf.d/cobbler-tftp.conf':
+    content => template('cobbler/cobbler-tftp.conf.erb'),
+    owner   => 'root',
+    group   => 'root',
+    mode    => '0644',
+    require => File['/etc/httpd/conf.d/'],
+    notify  => Service[$cobbler_web_service],
+  }
+
   service { $cobbler_web_service:
     ensure     => running,
     enable     => true,

deployment/puppet/cobbler/templates/cobbler-tftp.conf.erb

@@ -0,0 +1,8 @@
+Alias /cobbler/boot /var/lib/tftpboot
+
+<Directory /var/lib/tftpboot>
+  Options +Indexes +FollowSymLinks
+  AllowOverride None
+  Order allow,deny
+  Allow from all
+</Directory>

deployment/puppet/nailgun/templates/dnsmasq.dhcp-range.erb

@@ -2,3 +2,4 @@
 dhcp-range=<%= @range_name %>,<%= @dhcp_start_address %>,<%= @dhcp_end_address %>,<%= @dhcp_netmask %>,<%= @lease_time %>
 dhcp-option=net:<%= @range_name %>,option:router,<%= @dhcp_gateway %>
 dhcp-boot=net:<%= @range_name %>,pxelinux.0,boothost,<%= @next_server %>
+dhcp-option-force=210,http://<%= @next_server %>/cobbler/boot/