Use unpack to generate hex values.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Remove unused variables.

This was an attempt at using named parameters, but that's a Ruby 2.0 feature
and it wasn't done correctly anyway.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Add clipboard support.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>