Removing files we are not going to be using.
Adding make powershell script to run in windows.
added support for union of multiple filters
fixed bug - needed to expand hi0/lo0 range to include all ranges
Fix groupAll() after union reset.

This is also somewhat more efficient for large datasets, since it
recomputes group values from scratch rather than selecting all values,
removing them, and then adding them again.
Union of filters: return the dimension.

This is for consistency with non-union filters.
Add test for union of overlapping ranges.
Support custom filter functions.

This allows more esoteric filtering to occur e.g. multi-valued fields.
The filter function is called for every value, so this is slower than
incremental range filtering.
Custom filter function: notify filter listeners.
Using underscore shims in place of isArray, map, forEach for IE7/8

Added global._ to test, and added underscore to devDependencies
Updating crossfilter to use requireJS with dependency on lodash.