DOC: add missing parameters to npyio.genfromtxt, fix #2929

`loose` `missing` and `skiprows` were missing from the docstring of
`npyio.genfromtxt`. The later two are actualy deprecated, but were added
nonetheless.
DOC: two minor typos in genfromtxt
DOC: document equivalence of apply_over_axes and tuple axis ufuncs
DOC: dtype's compare requires aligned, not swapped arrays
Merge pull request #4430 from juliantaylor/apply-over-doc

DOC: document equivalence of apply_over_axes and tuple axis ufuncs
Merge pull request #4428 from jarondl/genfromtxt-doc

DOC: add missing parameters to npyio.genfromtxt, fix #2929
Merge pull request #4435 from jaimefrio/compare-doc

DOC: dtype's compare requires aligned, not swapped arrays