XBMC thumbnails fail to render

[wiggin15]

In XBMC view, the thumbnails of movies and TV shows fail to render:

The URI for xbmc/GetThumb raises the following exception:

2017-10-07 23:40:57 :: cherrypy.error.140245003550160 :: ERROR :: [07/Oct/2017:23:40:57] HTTP Traceback (most recent call last):
  File "/opt/htpc-manager/libs/cherrypy/_cprequest.py", line 656, in respond
    response.body = self.handler()
  File "/opt/htpc-manager/libs/cherrypy/lib/encoding.py", line 188, in __call__
    self.body = self.oldhandler(*args, **kwargs)
  File "/opt/htpc-manager/libs/cherrypy/_cpdispatch.py", line 34, in __call__
    return self.callable(*self.args, **self.kwargs)
  File "/opt/htpc-manager/modules/xbmc.py", line 215, in GetThumb
    return get_image(url, h, w, o, self.auth())
  File "/opt/htpc-manager/htpc/proxy.py", line 51, in get_image
    resize_image(image, height, width, opacity, resized)
  File "/opt/htpc-manager/htpc/proxy.py", line 107, in resize_image
    im.save(dest, imagetype)
  File "/usr/lib/python2.7/dist-packages/PIL/Image.py", line 1453, in save
    raise KeyError(ext) # unknown extension
KeyError: u'.0'

Using debug mode, I found that imagetype is None in proxy.py:resize_image, leaving PIL to try to determine the image file format from the filename, which ends with ".0" (the filename is created from the image properties. .0 is the opacity - so not helpful). There is an open Python issue about imghdr failing to detect the JPEG format: https://bugs.python.org/issue28591
We can use PIL itself to determine imagetype instead of using imghdr.