Similarly to http://www.python.org/sf/1515361, tries to
change the way ImportWarning behaves. The difference
between tha patches is that this one does not try to
produce a full list of all possible directories that
have not been imported. Instead, this patch only
provides number of candidate directories found, and
prints the first one, which hopefully is the most
likely candidate. Full description follows.

I tried to implement Jean-Paul Calderone's idea for the
following patch, plagiarizing Ralf W.
Grosse-Kunstleve's error text. It delays import warning
until end of search for modules, but remembers how many
potential modules (candidates without __init__.py) it
didn't import. I
didn't really try to analyze any conditions, instead I
simply assumed that wherever ImportWarning would be
issued, we have a suitable candidate, and saved it on
the stack. If nothing is found, Python emits
ImportWarning right before ImportError, and explains
what happened.