Ensure cleanup of Select Statement operations
Add Operation#inspect

Not necessary, but nice.
Use an unbuffered channel
Remove failing spec
Ensure the select statement is cleaned up
Don't init args that aren't needed
Simplify Operation#inspect
Complete under capacity pushes
Dry up code for completing buffered pushes
Dry up code pairing code
Select then complete
Cleanup
Merge pull request #19 from jridgewell/ensure-operation-cleanup

Ensure cleanup of Select Statement operations