Bump minimum memory requirement to 4GB

Author: Sean M. Collins

Vagrantfile

@@ -4,7 +4,7 @@ conf = {
     'ip_prefix' => '192.168.27',
     'box_name' => 'trusty',
     'box_url' => 'https://cloud-images.ubuntu.com/vagrant/trusty/current/trusty-server-cloudimg-amd64-vagrant-disk1.box',
-    'allocate_memory' => 1024,
+    'allocate_memory' => 4096,
     'cache_dir' => 'cache/',
     'ssh_dir' => '~/.ssh/',
     'devstack_repo' => 'git://github.com/openstack-dev/devstack.git',