packages: add lua-sec for prosody to support SSL/TLS (#4)
packages: add sudo
scripts: initial setup (#29, #4)): generate prosody TLS cert/key using openssl command line as 'prosodyctl cert generate' is only available on prosody 0.9+
scripts: initial setup (#29): use 521 bits for SSH ECDSA key length as 2048 is not supported
scripts: initial setup: place ssh keys in correct directory if root is the only user (#29)