crossfilter.bisect: support very large arrays.

This fixes an overflow issue when bisecting arrays larger than
1,073,741,824 in length.
Merge branch 'master' into sort-nan

Conflicts:
	tesseract.min.js
Fix the wiki link.
Merge branch 'master' into sort-nan
Fix bisect.right for incomparable values.

This fixes dimension.filterExact(…) for incomparable values, since it
uses bisect.right.  Incomparable values are assumed to be at the end of
the array, as implemented in sort(…).  The existing bisect.left does not
need modifying.
Fix NaNs in bisect.left and quicksort_by.
Optimise NaN test in insertion sort.
Add support for NaN or undefined group keys.

Previously, a group key of NaN or undefined would result in that value
going to the last non-NaN group.
Update dependencies.
Remove unused argument.
Merge branch 'bisect-large' into 1.1.1
add npm test script
add some people to package.json
add a CONTRIBUTING.md file for github
add .travis.yml for freebie ci
Update src/package.js.

Also, use a hash for author, contributors and maintainers.
Merge branch '1.1.1'
Fix incorrect sort behavior due to UglifyJS bug.

UglifyJS version 2.2.5 incorrectly performs the transformation:

  (x = f(…)) <= x → x >= (x = f(…))

This caused incorrect sorting behaviour when using crossfilter.min.js.

All tests now pass on crossfilter.min.js.
Update UglifyJS and revert workaround.

All tests pass on the minified version.  This version of UglifyJS fixes
a serious bug involving reordering of side-effects.
added support for union of multiple filters