post-deinstall:
  - Removing user/group is not a good idea. You can't know if the consul
    user/group has been created by the package or not; user can use it even
    for something else.

pre-deinstall:
  - User should decide h[ei]mself if (s)he wants to stop the service
    before uninstalling, it's his/her responsibility and it should not
    be handled automagically in pre-deinstall hook.
  - `&>` is not POSIX-sh compatible, it's a bashism.

* Update consul to 0.7.0
* Update init.d script to run configtest and create a log file

github.com/hashicorp/yamux
../../boltdb/bolt/db.go:85: undefined: maxMapSize
../../boltdb/bolt/db.go:85: invalid array bound maxMapSize
github.com/inconshreveable/muxado/proto/buffer

Now all invocations have following order of arguments (if present):

    addgroup -S -g ... GROUP
    adduser -S -u ... -D -H -h ... -s ... -G ... -g ... USER

Following rules have been applied:
- script starts with shebang !#/bin/sh followed by blank line,
- script ends with exit 0 prepended by blank line,
- only stderr of adduser, addgroup or passwd is redirected to /dev/null,
- getent passwd/group instances has been removed,
- manual checking of file and group existence has been removed,
- `|| true` instances has been removed.

Comments and line wrapping have been preserved.

This way we can avoid ugly default:

    Linux user,,,

It's only for consistency and to ease spotting lack of it.