Add reader for CONVERGE CFD files

This class reads CONVERGE CFD post files containing meshes, surfaces, and parcels. Each stream in a file is read as a top-level block and meshes, surfaces, and parcels are datasets under each stream block.

Cell data arrays associated with mesh cells can be individually selected for reading using the CellArrayStatus API.

Point data arrays associated with parcels can be individually selected for reading using the ParcelArrayStatus API.

Time series are supported. The reader assumes a time series is defined in a sequence of files that follow the naming convention

<prefix><zero-padded index>[_][<time>].h5

where the prefix is determined from the FileName property passed to the reader. The underscore and time elements are optional. The time value associated with each file is read from metadata in the file.

Added test and test data to exercise the reader.

Parallel data loading is not supported.