Add spec for `view`
Add a spec for omitting length from view()

nice to have
Merge pull request #19 from stuk/view-from-zero
Fix view observer function

The view observer now properly handles sliding windows.  The window will
slide or resize in response to length and position changes instead of
outright replacement.  The window will never grow up to more than twice
its length when sliding.
Merge pull request #26 from kriskowal/view-bug

Reimplement view