add NoIndex option to daemon

While investigating #5923, it became clear that for our specific use-case, namely creating/starting/removing containers in a rapid fashion, the TruncIndex is a source of short-lived allocations which bloat memory usage and degrade performance.

This patch adds a option `NoIndex` to be passed for container creation, which prevents the container from getting added to the TruncIndex.
@cyphar it may be self explanatory, but I have no clue what this does.  Does it prevent docker from talking to the official on-line docker registry?