supybot-test: Display a full traceback when there is an error while importing a plugin.

scripts/supybot-test

@@ -38,6 +38,7 @@ started = time.time()
 
 import supybot
 import logging
+import traceback
 
 # We need to do this before we import conf.
 if not os.path.exists('test-conf'):
@@ -198,7 +199,8 @@ if __name__ == '__main__':
         try:
             pluginModule = plugin.loadPluginModule(pluginName)
         except (ImportError, callbacks.Error) as e:
-            sys.stderr.write('Failed to load plugin %s: %s\n' % (pluginName,e))
+            sys.stderr.write('Failed to load plugin %s:' % pluginName)
+            traceback.print_exc()
             sys.stderr.write('(pluginDirs: %s)\n' %
                              conf.supybot.directories.plugins())
             continue