Add a --verbose option for listing labels

lib/ghi/commands/label.rb

@@ -16,7 +16,7 @@ def options
 usage: ghi label <labelname> [-c <color>] [-r <newname>]
    or: ghi label -D <labelname>
    or: ghi label <issueno(s)> [-a] [-d] [-f] <label>
-   or: ghi label -l [<issueno>]
+   or: ghi label -l [<issueno>] [-v]
 EOF
           opts.separator ''
           opts.on '-l', '--list [<issueno>]', 'list label names' do |n|
@@ -38,6 +38,9 @@ def options
             assigns[:name] = name
             self.action = 'update'
           end
+          opts.on '-v', '--verbose', 'show color values for labels' do |v|
+            self.verbose = true
+          end
           opts.separator ''
           opts.separator 'Issue modification options'
           opts.on '-a', '--add', 'add labels to issue' do
@@ -84,6 +87,9 @@ def index
         else
           puts labels.map { |label|
             name = label['name']
+            if self.verbose
+              name += " ##{label['color']}"
+            end
             colorize? ? bg(label['color']) { " #{name} " } : name
           }
         end