DOC: add guidelines for building the docs
DOC: add section contributing to pandas

+ link to README.rst in /docs
DOC/BUG: Fix documentation for `infer_datetime_format` #6073

Fix formatting typos and ensure the "foo.csv" ipython processing works.
Merge pull request #6078 from danbirken/infer-dt-doc-fix

DOC/BUG: Fix documentation for `infer_datetime_format` #6073
Merge pull request #5996 from jorisvandenbossche/doc-guide

DOC: add guidelines for building the docs
BLD/DOC: report context on warnings and add :okwarning: to ipython_directive
Merge pull request #6082 from y-p/PR_ipython_directive

BLD/DOC: report context on warnings and add :okwarning: to ipython_directive
DOC/BLD: ipython_directive cleanups
DOC: minor doc changes
Added 'Experimental' to Docstrings
Merge pull request #6084 from jacobschaer/master

Added 'Experimental' to Docstrings For GBQ
DOC: supress warnings with okwarning in whatsnew
BUG: array_equivalent was not passing its own doctest. The examples showed lists being passed to array_equivalent. array_equivalent expects ndarrays only.
Merge pull request #6088 from unutbu/fix-equivalent

BUG: array_equivalent was not passing its own doctest.
Merge pull request #6086 from jorisvandenbossche/doc-warnings

DOC: suppress warnings with okwarning in whatsnew
DOC/BLD: ipython_directive cleanups
BUG: ensure plt is imported before it's used in hist_frame