[valadoc] valadoc: fix --help output for --doclet option.

[Florian Brosch <flobrosch src gnome org>]

commit 5cc5ae7dd84d19b3da9b3db2c83e7c95b300d58b
Author: Evan Nemerson <evan coeus-group com>
Date:   Tue May 4 22:52:56 2010 +0200

    valadoc: fix --help output for --doclet option.

 src/valadoc/valadoc.vala |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/valadoc/valadoc.vala b/src/valadoc/valadoc.vala
index 02ff730..5dc001a 100755
--- a/src/valadoc/valadoc.vala
+++ b/src/valadoc/valadoc.vala
@@ -83,7 +83,7 @@ public class ValaDoc : Object {
 		{ "wiki", 0, 0, OptionArg.FILENAME, ref wikidirectory, "Wiki directory", "DIRECTORY" },
 		{ "deps", 0, 0, OptionArg.NONE, ref with_deps, "Adds packages to the documentation", null },
 		{ "doclet-arg", 'X', 0, OptionArg.STRING_ARRAY, ref pluginargs, "Pass arguments to the doclet", "ARG" },
-		{ "doclet", 0, 0, OptionArg.STRING, ref pluginpath, "plugin", "Name of an included doclet or path to custom doclet" },
+		{ "doclet", 0, 0, OptionArg.STRING, ref pluginpath, "Name of an included doclet or path to custom doclet", "PLUGIN"},
 
 		{ "no-protected", 0, OptionFlags.REVERSE, OptionArg.NONE, ref _protected, "Removes protected elements from documentation", null },
 		{ "internal", 0, 0, OptionArg.NONE, ref _internal, "Adds internal elements to documentation", null },