Update README.md

Added a book
Update README.md

correct the link error for 99 problems
add qcheck to the readme
http://cranialburnout.blogspot.ca/: a blog about game development in
OCaml.
Merge pull request #15 from MassD/patch-1

Update README.md
Merge pull request #20 from Armael/master

http://cranialburnout.blogspot.ca/: a blog about game development in OCaml.
Merge pull request #19 from c-cube/master

add qcheck to the readme
Merge pull request #16 from MassD/patch-2

Update README.md
Added more compilers in OCaml.