fix formatting for Sphinx

bold italic isn't possible...

Author: basnijholt

README.rst

@@ -6,7 +6,7 @@
 |PyPI| |Conda| |Downloads| |Pipeline status| |DOI| |Binder| |Gitter|
 |Documentation| |GitHub|
 
-** *Adaptive*: Parallel active learning of mathematical functions.**
+  *Adaptive*: parallel active learning of mathematical functions.
 
 ``adaptive`` is an open-source Python library designed to
 make adaptive parallel function evaluation simple. With ``adaptive`` you
@@ -126,7 +126,7 @@ Citing
 
 If you used Adaptive in a scientific work, please cite it as follows.
 
-.. code::
+.. code:: bib
 
     @misc{Nijholt2019,
       doi = {10.5281/zenodo.1182437},