DOC: fix link to str.get_dummies
Merge pull request #6278 from jorisvandenbossche/doc-fix-dummies-link

DOC: fix link to str.get_dummies
PERF: enhance tseries getitem indexing

PERF: micro optimzations in inference

API/CLN: core.internals.apply now only takes kwargs; makes code a bit simpler

CLN: wrap core/common/isnull into more direct Block.isnull

PERF: fast path series block operations