[docs] update Cygwin readme. resolves RT#51944
[docs] update Cygwin readme.
resolves RT#51944



git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@34718 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot