DOC: document read_csv fastpath for iso8601 datetime strings
Merge pull request #5993 from y-p/PR_doc_iso8601_fast_path

DOC: document read_csv fastpath for iso8601 datetime strings
DOC: Document fast path in to_datetime GH4826
DOC: typos
Only recast if datetime; use astype instead of view
Merge pull request #5998 from TomAugspurger/interpolate-datetime-fix

BUG: use astype for scipy datetime interpolation
TST: add regression test for interpolate #5977
BLD: make scatter_ci after_script.sh standalone
TST: add skip_scipy
TST: add skip_pchip
DOC: add sklearn-pandas to pandas ecosystem section
Merge pull request #6001 from y-p/PR_doc_ecosystem

DOC: add sklearn-pandas to pandas ecosystem section
BUG: possible fsync error when filno is negative (GH5999)
Merge pull request #6004 from jreback/pytables_fsync

BUG: possible fsync error when filno is negative (GH5999)
TST: pytables test changes to work in 3.1rc1
Merge pull request #6005 from jreback/pytables_3.1

TST: pytables test changes to work in 3.1rc1
DOC: Clarified documentation for MultiIndexes

Add examples and rewrite an awkwardly-written bit

Cross-reference MultiIndex constructors
Merge pull request #5964 from felixlawrence/improve-multiindex-docs

DOC: Clarified documentation for MultiIndexes
DOC: release.rst mention IPython warnings in qtconsole fix and workaround GH5922
CLN: remove util.counter, duplicates compat