get RangeError when adding interval with 1073741824 / 1073741825

[brycehanscomb]

The following line produces a RangeError:

new IntervalTree(1).add([1073741824, 1073741825, 'hello']);

The exact error in Chrome is:

Uncaught RangeError: Maximum call stack size exceeded - SortedList.js:26

[fredericgermain]

I got this when I initialize IntervalTree with a bad value (actually, the max value I intented to have in the tree).
When initializing with the medium value (max-min)/2, it was ok

[occidens]

When the midpoint of intervals was calculated by bit shifting (prior to f7166f0), the error that @brycehanscomb encountered was due to the fact, when bit shifting, Java considers integers to be in a 32-bit signed representation. 1,073,741,824 + 1,073,741,825 = 2,147,483,648, which is greater than the largest 32-bit signed integer, 2,147,483,647. Thus 1073741824 + 1073741825 >> 1 gives the wrong answer because it wraps around to a negative number.

@fredericgermain, by the time you looked at this, you were seeing a different problem that was due to a typo in the new code for finding the interval midpoints. PR #11 should resolve this. And using / 2 instead of >> 1 to divide by 2 means that the full allowable range of integers can be used.