Ignore inconsequential range changes.
Idempotent cancelation

Ignore subsequent requests to cancel an already canceled event listener.
Improve event handler error cases

Throws errors if the handler can't be called or invoked in any way.

Also fix a bug in range changes where the context object was not passed
to the event handler.
Add Object.from
0.1.6
Shim RegExp
Return this from deleteEach
Implement a max Heap
Document peek and poke
Implement Dict reduceRight
Clean up zip, unzip, enumerator, sum, every

-   Add enumerate to Arrays
-   Add enumerate to generic collections
-   Expose transpose (originally in generic collections) as Array.unzip
-   Rename Iterator transpose to unzip
-   Distinguish Iterator enumerate from enumerateIterator
-   Remove superfluous iterator implementations of every and some
-   Inherit explicit generics into Iterator from GenericCollection.
    Some are not applicable, like addEach and deleteEach.
-   Update documentation.
Allow equals override in generic deleteEach
Allow default fallback on Array get
Allow nested equals override in Array equals
Remove obsolete note on generic inheritance in SortedMap
0.1.7
Add cross-reference checklist