Merging in latest from upstream (HDFFV/hdf5:refs/heads/develop)
* commit '7f0c0134166275c0745e0e65f9d81b4de72d5ce2':
Remember the info for the last ID looked up for a given ID type.
Eliminate allocating file & memory offset & length arrays when performing I/O on a single element.
Remove redundant metadata cache tagging from some low-level internal chunk functions. The metadata cache tagging has already been done by routines further up the call stack.