DOC: integrate: move the quad_explain() text to quad() docstring

There's no real reason to keep the documentation in a different place.
DOC: optimize: reformat show_options + fix links to it

Make show_options look better in HTML, and make the links to it
clickable.
DOC: clarify the docstring of stats.randint.  Also fix the 4th moment.
ENH: moments for the zipf distribution
Merge branch 'pr/2904' into master.

See https://github.com/scipy/scipy/pull/2904
Merge pull request #2970 from pv/quad-docc

DOC: fix up quad() and show_options() docstrings
Fix a minor typo
WIP ENH: Add "limit" argument to dijkstra
Merge pull request #2985 from thenovices/fix-typo

Fix a minor typo
TST: remove all docstrings from test functions for stats.morestats
BUG: runtests: chdir away from root when running tests

This makes it possible for subprocesses possibly launched by the test to
import the module under testing.

Also, do not pass --debug to setup.py build, since this can make the
build require Python debug symbols to be installed (on windows).
DOC: linalg: don't recommend np.linalg.norm
TST: add tests for stats.probplot, and fix minor issues and docs.

Closes gh-677 (Statistics Review).
MAINT: clean up some more code in stats/morestats.py
ENH: Limiting works
FIX: Fix old np test
Merge pull request #2986 from pv/runtests-fix

BUG: runtests: chdir away from root when running tests
Add Eclipse editor project files to .gitignore
Add parenthesis in csgraph tutorial title to be consistent
Add missing return statements in Python 3 kdtree code