Fix indentation on markdown (#2929)
Fix indentation on markdown (#2929)

* Fix indentation on markdown

- Too many spaces causes sphinx to blockquote the
links instead of using an unordered list.
- Change links to absolute to work in GH and readthedocs
balopat/Cirq,quantumlib/Cirq,quantumlib/Cirq,quantumlib/Cirq,balopat/Cirq,balopat/Cirq,quantumlib/Cirq,quantumlib/Cirq