DOC: Clean Cookbook Issues: Tabs, expanded_apply, axis aliasing, etc.
Merge pull request #8535 from jnmclarty/cookbook_inline_examples

DOC: Clean up Sphinx Issues, fix tabs, in Cookbook
Merge pull request #8544 from mtkni/master

PERF: Performance improvement for MultiIndexes with a DatetimeIndex levels
DOC: v0.15.0 corrections
PERF: Slowness in multi-level indexes with datetime levels

Special case handling of sliced multi indexes, where there the length of the level values may exceed the length of the index.