[enh] gettext in self ip plugin

searx/plugins/self_ip.py

-
+from flask.ext.babel import gettext
 name = "Self IP"
-description = "Display your source IP address"
+description = gettext('Display your source IP address if the query expression is "ip"')
 default_on = True
 
 
+# attach callback to the pre search hook
+#  request: flask request object
+#  ctx: the whole local context of the pre search hook
 def pre_search(request, ctx):
     if ctx['search'].query == 'ip':
         x_forwarded_for = request.headers.getlist("X-Forwarded-For")
             ip = request.remote_addr
         ctx['search'].answers.clear()
         ctx['search'].answers.add(ip)
+        # return False prevents exeecution of the original block
         return False
     return True