fixing some systemd configs

1) I removed the curly-brackets from the tlsdated.service file because otherwise DAEMON_OPTS="-f some/file" ends up getting sent to tlsdated as one argument instead of two. (and DAEMON_OPTS="" is interpreted as one argument instead of zero.)

2) I copy the /etc/default/tlsdated file to where it's being expected, because otherwise systemd throws an error when it looks for EnvironmentFile.

Never done any debian packaging, so the style's probably off. Probably the .service and .default file should be moved in the Makefile, since they're in upstream tlsdate now?