message: Add autoconf to the list of prereqs to ubuntu/debian build instructions
diff: @@ -13,7 +13,7 @@ Run the following to install the base dependencies for building:
  ```bash
  -sudo apt-get install build-essential libtool autotools-dev automake pkg-config libssl-dev libevent-dev bsdmainutils git
  +sudo apt-get install build-essential libtool autotools-dev autoconf automake pkg-config libssl-dev libevent-dev bsdmainutils git
  ```
  On at least Ubuntu 14.04+ and Debian 7+ there are generic names for the
  