Fix readme section headers (#3176)

README.rst

@@ -17,6 +17,7 @@ circuits and running them against quantum computers and simulators.
     :target: https://readthedocs.org/projects/cirq/versions/
     :alt: Documentation Status
 
+
 Installation and Documentation
 ------------------------------
 
@@ -33,6 +34,7 @@ Documentation for the latest **stable** version of cirq (what you get if you ``p
 
 For the latest news regarding Cirq, sign up to the `Cirq-announce email list <https://groups.google.com/forum/#!forum/cirq-announce>`__!
 
+
 Hello Qubit
 -----------
 
@@ -68,17 +70,19 @@ Example output:
   Results:
   m=11000111111011001000
 
+
 Feature requests / Bugs / Questions
---------------------------------
+-----------------------------------
 
 If you have feature requests or you found a bug, please `file them on Github <https://github.com/quantumlib/Cirq/issues/new/choose>`__.
 
 For questions about how to use Cirq post to
 `Quantum Computing Stack Exchange <https://quantumcomputing.stackexchange.com/>`__ with the
 `cirq <https://quantumcomputing.stackexchange.com/questions/tagged/cirq>`__ tag.
 
+
 Cirq Contributors Community
-------------------
+---------------------------
 
 We welcome contributions! Before opening your first PR, a good place to start is to read our
 `guidelines <https://github.com/quantumlib/cirq/blob/master/CONTRIBUTING.md>`__.
@@ -107,6 +111,7 @@ For a powerful quantum circuit simulator that integrates well with Cirq, we reco
 
 Finally, `ReCirq <https://github.com/quantumlib/ReCirq>`__ contains real world experiments using Cirq.
 
+
 Alpha Disclaimer
 ----------------