Restores .md files to the master branch.

* R/README.md:

 Changes to be committed:
	new file:	R/README.md
	deleted:	R/README.org
	renamed:	README.org -> README.md
	new file:	data/README.md
	deleted:	data/README.org
	new file:	man/README.md
	deleted:	man/README.org
	renamed:	tests/README.org -> tests/README.md