Configuration problems should print errors, not stack traces.

[jordansissel]

Raising unexpected exceptions will often produce a crash-like behavior which prints the exception and a stack trace. Stack traces are not helpful content in situations where a user has made a configuration error.

In most cases, known configuration issues should raise either FPM::Package::InvalidArgument or FPM::InvalidPackageConfiguration. (Honestly, I have forgotten why these two exceptions aren't just a single exception type).

---

Before:

% bin/fpm -s empty -t deb --deb-systemd /tmp/foo.test -n example
/Users/jls/projects/fpm/lib/fpm/package/deb.rb:528:in `block in output': Invalid systemd unit file extension: .test. Expected .service or .timer, or no extension. (ArgumentError)
	from /Users/jls/projects/fpm/lib/fpm/package/deb.rb:519:in `each'
	from /Users/jls/projects/fpm/lib/fpm/package/deb.rb:519:in `output'
	from /Users/jls/projects/fpm/lib/fpm/command.rb:508:in `execute'
	from /Users/jls/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/clamp-1.0.1/lib/clamp/command.rb:68:in `run'
<remainder of stack trace is omitted>

After:

% bin/fpm -s empty -t deb --deb-systemd /tmp/foo.test -n example
Invalid package configuration: Invalid systemd unit file extension: .test. Expected .service or .timer, or no extension. {:level=>:error}