[20160827142755] Updated AMIs, Memcached, and General Enhancements

[ddollar]

• #1123 Make convox init generate v2 templates [@awsmsrc]
• #1146 Update AWS Go SDK to version 1.4.3 [@MiguelMoll]
• #1152 Add memcached service [@ddollar]
• #1157 Update ECS AMIs [@ddollar]