Fixed login/logout/logged as items in metanav

Most of the issues were caused by Trac's clever plugin
system where classes implementing INavigationContributor
all contribute to the metanav. Plugins can then override
existing links by making sure they pass the same name
(second element in the yielded tuple in get_navigation_items()).
On top of that, trac.ini can override any item by specifying
a <item name>.label configuration.

Rather than trying to figure this all out, I've opted to
hardcode the navigation menu in the HTML. This has the nice
side-effect of removing the dependency on the forked trac-github.

This commit therefore includes a revert of
d8760ad.

Fixes #51

requirements.txt

@@ -16,10 +16,7 @@ https://trac-hacks.org/browser/xmlrpcplugin/trunk?rev=18591&format=zip
 oauthlib==2.1.0
 requests==2.20.1
 requests-oauthlib==1.0.0
-# trac-github is unmaintained at this time and not compatible with Trac 1.4
-# See issue https://github.com/trac-hacks/trac-github/issues/136 for example
-# So obviously the solution is a fork, this one will surely never go unmaintained
-trac-github @ git+https://github.com/bmispelon/trac-github.git@trac-1.4
+trac-github==2.3
 
 gunicorn==19.10.0
 sentry-sdk==1.11.0

trac-env/conf/trac.ini

@@ -92,13 +92,8 @@ timeline.order = 4.0
 wiki.order = 5.0
 
 [metanav]
-about = disabled
-github_login.order = 1.0
-help = disabled
-login.label = DjangoProject Login
-login.order = 2.0
-logout.order = 3.0
-prefs.order = 4.0
+; The metanav is hardcoded in templates/django_theme.html
+; because it was too hard to make the login plugins play nice with each other
 
 [mimeviewer]
 enscript_modes = text/x-dylan:dylan:4

trac-env/templates/django_theme.html

@@ -17,7 +17,26 @@
 
 # macro main()
 <div role="main">
-  ${navigation('metanav')}
+  <div id="metanav" class="nav">
+    <ul>
+      # if req.is_authenticated:
+        <li>Logged in as ${req.authname}</li>
+        <li>
+          <form action="/github/logout" method="post" id="logout" class="trac-logout">
+            <button type="submit">Logout</button>
+            <input type="hidden" name="__FORM_TOKEN" value="${req.form_token}">
+          </form>
+        </li>
+      # else
+        <li><a href="/github/login">GitHub Login</a></li>
+        <li><a href="/login">DjangoProject Login</a></li>
+      # endif
+      <li><a href="${req.href.prefs()}">Preferences</a></li>
+      # if req.perm.has_permission('XML_RPC'):
+        <li><a href="${req.href.rpc()}">API</a></li>
+      # endif
+    </ul>
+  </div>
   ${navigation('mainnav')}
   <div id="main" ${{'class': {
                     'uisymbols': req.session.get('ui.use_symbols'),