Some templates like OTP apps are usable within releases, so the text
does remain a bit vague, but hopefully less than before.

- The OTP app template now adds the supevisor
- The default apps_dir value does not contain the trailing '/' that the
  template index already added.

The first variable can be unkeyed and the provider will sub in the
variable name 'name'. Additionally, the built-in templates and
documentation have been updated so that 'appid' is now 'name' and the
alternative commands are shown.

This totally breaks compatibility with rebar2, and maybe it shouldn't
have.

When a node is configured with -sname the REMSH_NAME_PART argument should be defined with using command 'hostname' but error occurs due extra space

RUNNER_SCRIPT variable is not initialized in simplenode.runner and it's
referenced when calling sudo.

To avoid problems with REMSH node being visible from another nodes
starts it in hidden mode (erl -hidden).

When a node is configured with -sname in app.config or sys.config the
REMSH_NAME_ARG and REMSH_REMSH_ARG arguments are incorrect due the
assumption that the node name always contains '@'.

To fix the bug, the script tries to find '@' and then compose the
arguments acording to node name type. If in long name mode the
script can't compose a correct node name exits with warning.