Adds type_caster support for std::deque. (#1609)
* Adds std::deque to the types supported by list_caster in stl.h.
* Adds a new test_deque test in test_stl.{py,cpp}.
* Updates the documentation to include std::deque as a default
supported type.diff --git a/docs/advanced/cast/stl.rst b/docs/advanced/cast/stl.rst
index 468bd2c..e48409f 100644
--- a/docs/advanced/cast/stl.rst
+++ b/docs/advanced/cast/stl.rst
@@ -5,7 +5,7 @@
====================
When including the additional header file :file:`pybind11/stl.h`, conversions
-between ``std::vector<>``/``std::list<>``/``std::array<>``,
+between ``std::vector<>``/``std::deque<>``/``std::list<>``/``std::array<>``,
``std::set<>``/``std::unordered_set<>``, and
``std::map<>``/``std::unordered_map<>`` and the Python ``list``, ``set`` and
``dict`` data structures are automatically enabled. The types ``std::pair<>``