Pyby

Adds support for the following:

* Objectsend
* Enumerablereject
* Enumerableinject with Enumerablereduce as an alias

Bug fix release to handle non-mapping Enumerables containing tuples, e.g. a list of tuples.

Adds support to `Enumerable` (and hence `EnumerableList` and `EnumerableDict`) for `filter/select`.

Initial release into the wild.

Implements `Enumerable`, `EnumerableList`, `EnumerableDict` with support for:

* collect/map (no args)
* collect/map (callable args)
* compact
* each (no args)
* each (callable arg)
* first (no args)
* first (n elements)
* take

Also implements `Enumerator` with support for:

* next
* peek
* rewind