Add a new "tail -f stderr" link to the Web UI

Closes Supervisor#254
Closes Supervisor#1027
Closes Supervisor#1173

Author: mnaberez

CHANGES.rst

@@ -11,6 +11,10 @@
 
 - Web UI buttons no longer use background images.  Patch by Dmytro Karpovych.
 
+- The Web UI now has a link to view ``tail -f stderr`` for a process in
+  addition to the existing ``tail -f stdout`` link.  Based on a
+  patch by OuroborosCoding.
+
 - The HTTP server will now send an ``X-Accel-Buffering: no`` header in
   logtail responses to fix Nginx proxy buffering.  Patch by Weizhao Li.
 

supervisor/ui/stylesheets/supervisor.css

@@ -78,7 +78,7 @@ html, body {
   min-height: 100%;
   height: auto !important;
   height: 100%;
-  width: 782px;
+  width: 850px;
   margin: 0 auto -31px;
 }
 #footer,

supervisor/web.py

@@ -259,18 +259,23 @@ def actions_for_process(self, process):
             'href': 'index.html?processname=%s&action=clearlog' % processname,
             'target': None,
         }
-        tailf = {
-            'name': 'Tail -f',
+        tailf_stdout = {
+            'name': 'Tail -f Stdout',
             'href': 'logtail/%s' % processname,
             'target': '_blank'
         }
+        tailf_stderr = {
+            'name': 'Tail -f Stderr',
+            'href': 'logtail/%s/stderr' % processname,
+            'target': '_blank'
+        }
         if state == ProcessStates.RUNNING:
-            actions = [restart, stop, clearlog, tailf]
+            actions = [restart, stop, clearlog, tailf_stdout, tailf_stderr]
         elif state in (ProcessStates.STOPPED, ProcessStates.EXITED,
                        ProcessStates.FATAL):
-            actions = [start, None, clearlog, tailf]
+            actions = [start, None, clearlog, tailf_stdout, tailf_stderr]
         else:
-            actions = [None, None, clearlog, tailf]
+            actions = [None, None, clearlog, tailf_stdout, tailf_stderr]
         return actions
 
     def css_class_for_state(self, state):