test calling isa() on a nonsense value
add TODO test for not issuing a warning when isa() was properly invoked as a method

see https://rt.cpan.org/Ticket/Display.html?id=97468
fix typo in class name
use vars -> our
remove unneeded shebangs
whitespace
mark the $recursing global as more obviously for private use only
tighten the scope where warnings are loosened
remove redundant pragma
Do not warn about callers from within Test::Builder (RT#97468)

starting with version 1.301001, Test::Builder itself uses ->isa in its
implementation.  We are incapable of distinguishing between a real method call
and an invocation as a function, so we warn in all situations in verbose mode.
Exempting Test::Builder entirely is the only way to get through our own test
suite in verbose mode (last section of t/basic.t).

e.g.  http://www.cpantesters.org/cpan/report/3ee883b4-10fa-11e4-97f6-9b514fc05230
make all subs private - no user-servicable parts inside
convert to my plugin bundle
weave pod
merge all Yuvals into one
canonicalize changelog timestamps
UNIVERSAL-isa-1.20140824

    - fix tests that started failing with new development versions of
      Test::Builder (RT#97468)