Make 'or' and 'and' able to exit early.
Implemented in Feldspar.Vector.PullPush
Spelling
Add a function 'iterate' to Sequential.
Add some useful functions to Stream.
This patch includes a Num instance and the function 'pre'.
Generalize the type of (++). The argument vectors need not be the same kind
of vector. It is enough that they are both pushy.