Xiaoya add local cache

[xiaoyachong]

I added local image caching by introducing TiledLocalImagePublisher to the Arroyo operator. When a RawFrameEvent is received, its RawFrameEvent.image is saved to the local Tiled server.

For example, if the original RawFrameEvent.tiled_url is:
http://tiled-dev.nsls2.bnl.gov/api/v1/array/full/79b18ce7-c6a9-4c25-8b7c-7d3c5a57a536/streams/primary/pil2M_image?slice=0:1,0:1679,0:1475

then the image is stored on the local Tiled server with a new URL of the form:
http://tiled:8000/api/v1/array/full/{container_name}/79b18ce7-c6a9-4c25-8b7c-7d3c5a57a536/streams/primary/pil2M_image/frame0?slice=0:1,0:1679,0:1475

Here:
{container_name} (e.g., live_data_cache) is added at the root.
Unlike the original Tiled URLs, where multiple images may be stored in a single container, in the local Tiled server each container holds only one image, so an additional frame{id} suffix is appended.

The related issue can be found at issue #62
.