Introduce '--quiet'/-q' option to the 'status' subcommand

This option will bypass the prompt (and the routine) to remove an old
PID file.

Fixes #10.
Complain precisely to stderr in the event of invalid PID file content

* A blank PID file
* A PID file with content other than an integer expression
* A PID file containing an integer that overflows the legal PID range

Fixes #12.
Improve the usability of the prompt to remove an old PID file

* Accept either "y" or "yes", ignoring case
* Accept a response on the same line as the prompt
* Indicate what the default response is
Merge pull request #11 from njonsson/status-quiet-option

Introduce '--quiet'/-q' option to the 'status' subcommand
Merge pull request #13 from njonsson/pidfile-error-handling

Complain precisely to stderr in the event of invalid PID file content
Merge pull request #14 from njonsson/usability-of-remove-old-pidfile-prompt

Improve the usability of the prompt to remove an old PID file
Bump version.
Introduce '--quiet'/-q' option to the 'stop' subcommand

This option will bypass the prompt (and the routine) to remove an old
PID file.

Fixes #15.
Merge pull request #16 from njonsson/stop-quiet-option

Introduce '--quiet'/-q' option to the 'stop' subcommand
Bump version.