Log Message:
py-sphinx: updated to 1.7.7

Release 1.7.7:

Bugs fixed
* document not in toctree warning when including files only for parallel
  builds
* LaTeX: reduce "Token not allowed in a PDF string" hyperref warnings \ 
in latex
  console output
* LaTeX: suppress "remreset Warning: The remreset package is obsolete" \ 
in latex
  console output with recent LaTeX
* PDF output: usage of PAPER environment variable is broken since Sphinx
  1.5
* LaTeX: fix the :confval:`latex_engine` documentation regarding Latin Modern
  font with XeLaTeX/LuaLateX
* autodoc: Fix wrong type annotations for complex typing
* autodoc: Optional types are wrongly rendered
* autodoc crashed by ForwardRef types
* autodoc: No docs generated for functools.partial functions
* autodoc: ``getargspec()`` raises NameError for invalid typehints
* imgmath: math_number_all causes equations to have two numbers in html
* sphinx-quickstart blank prompts in PowerShell