Provided a __hash__ method for IntegerPoint.
Allow integer runahead limits.
Satellite example suite upgrade for recent changes.
Added the integer satellite example as a new test.
Merge pull request #1152 from hjoliver/integer-cycling.hash-method

Provided a __hash__ method for IntegerPoint.
Some minor User Guide fixes (typos, line length overruns...).
More CUG updates.

Removed some outdated material on "asynchronous tasks"; consistent use of
section references; changed graph "VALIDITY" heading to "RECURRENCE".