Inf appears to be unspec'ed

[Mark Stosberg]

The formal definition of "Inf" appears to be missing from the spec
documents. Since I'm not exactly sure how Perl 6 treats "Inf", I'll
leave submitting this patch to someone else.

Once the spec is added, a smart link to it should be added from:
t/builtins/math/infinity.t

Mark

[Mark Stosberg]

Along the same lines, I couldn't find a spec for either "not" or "true",
which both have passing tests for pugs in t/builtins/bool/

Mark

[Mark Stosberg]

TimToady caught me on IRC and pointed out where "Inf", "not" and "true"
are mentioned in the spec, if only briefly. Smart links have been added
for them now.

Mark