Clarification in readme (for real this time)

Cleaned the cross-branch noise I'd let creep in.
Missing comments added to chan-directional. Some trimming and reordering.
ShuffledSequence is now as generic as possible, using any CollectionType whose Index is a RandomAccessIndexType

In other words, it works for Array and Slice. Not sure what else qualifies.
Added a framework target to the project. Eliminated the read/receive and write/send dichotomies.

Some fixes to access modifiers and to comments followed.

The directional channel classes still have "Read" and "Write" in their names; not sure if there is a really good name for them.
Merge recent changes from branch master into branch channel-select