Main

Adding missing include to write_test. Also correcting read_test
units.

Adding simple single threaded write_test utility.

Additional read_test uring adjustments.

Clean up read test code. Add liburing 2.4 as external source.

read_test: Added SynchronizedCounter class.

read_test: Add helper functions to read and validate the current kernel
version. Also add validation for the uring read type to ensure that the
kernel version is >= 5.6.

read_test: Add optional comment block to output input data one chunk per
file. This can be used to verify that the output data matches the input
data.

read_test: add new uring read method to read_test. It uses (requires)
liburing and a kernel >= 5.6.

Correct multiply by integer operator. Also add test cases.

Use boost::program_options for the main program.