[PATCH 1 of 3] extdiff: register the configuration generated commands with a help category

[Matt Harbison]

# HG changeset patch
# User Matt Harbison <matt_harbison at yahoo.com>
# Date 1543888788 18000
#      Mon Dec 03 20:59:48 2018 -0500
# Node ID faaf565508106fb08151ee169b9aa4b937374cc1
# Parent  bda0cb4839fb8618118e5dc7ab4b6742992eabd4
extdiff: register the configuration generated commands with a help category

Otherwise, 'extdiff' shows up under file management and the rest of the commands
are at the bottom under 'Uncategorized'.

diff --git a/hgext/extdiff.py b/hgext/extdiff.py
--- a/hgext/extdiff.py
+++ b/hgext/extdiff.py
@@ -429,6 +429,7 @@ def uisetup(ui):
             if args:
                 cmdline += ' ' + args
         command(cmd, extdiffopts[:], _('hg %s [OPTION]... [FILE]...') % cmd,
+                helpcategory=command.CATEGORY_FILE_CONTENTS,
                 inferrepo=True)(savedcmd(path, cmdline))
 
 # tell hggettext to extract docstrings from these functions: