ENH: Convert README from ReStructured Text to MarkDown #228

Job	Run time
build-macos-python-packages (38)	15m 19s
build-linux-python-packages (38)	4m 26s
build-macos-python-packages (39)	14m 58s
build-test-cxx (ubuntu-22.04)	10m 22s
build-linux-python-packages (39)	4m 39s
build-macos-python-packages (310)	1s
build-test-cxx (windows-2022)	12m 43s
build-linux-python-packages (310)	3m 44s
build-windows-python-packages (8)	15m 11s
build-test-cxx (macos-12)	10m 42s
build-macos-python-packages (311)	1s
build-linux-python-packages (311)	3m 46s
build-windows-python-packages (9)	15m 12s
build-windows-python-packages (10)	12m 31s
build-windows-python-packages (11)	11m 30s
	2h 15m 5s

Provide feedback