Fixed: CPApplicationTest.

A recent commit broke it.
Argument check CPIndexSet indexSetWithIndex:.

Without this check, an index set could be initialised with NaN which would later lead to an infinite loop when enumerating the index set.

This error makes the error early and explicit.
Merge branch 'refs/heads/0.9.6'
Merge branch 'master' of github.com:cappuccino/cappuccino