Feature #391 - legendary enhancement

- Added feature #391, now the 'task color legend' command will show
  samples of all the defined colors and color rules from your .taskrc
  and theme.

doc/man/task-color.5

@@ -193,6 +193,15 @@ color1, and proceed.  Note that red and color1 are not quite the same.
 Note also that there is no bold or bright attributes when dealing with 256
 colors, but there is still underline available.
 
+.SH LEGEND
+Task will show examples of all defined colors used in your .taskrc, or theme,
+if you run this command:
+
+    $ task color legend
+
+This gives you an example of each of the colors, so you can see the effect,
+without necessarily creating a set of tasks that meet each of the rule criteria.
+
 .SH RULES
 Task supports colorization rules.  These are configuration values that specify
 a color, and the conditions under which that color is used.  By example, let's

doc/man/task.1

@@ -133,8 +133,9 @@ Exports all tasks in iCalendar format.
 Redirect the output to a file, if you wish to save it, or pipe it to another command.
 
 .TP
-.B color [sample]
-Displays all possible colors, or a sample.
+.B color [sample | legend]
+Displays all possible colors, a named sample, or a legend containing all
+currently defined colors.
 
 .TP
 .B version