Merge pull request numpy#19857 from bzah/feature/rewrite_percentile

MAINT, ENH: Refactor percentile and quantile methods

Author: seberg

doc/release/upcoming_changes/19857.improvement.rst

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+Add new linear interpolation methods for ``quantile`` and ``percentile``
+------------------------------------------------------------------------
+
+``quantile`` and ``percentile`` now have 13 linear interpolation methods,
+nine of which can be found in the scientific literature.
+The remaining methods are NumPy specific and are kept for backwards
+compatibility. The default is "inclusive" (method 7), whose behavior is equivalent
+to the former default "linear".