Backport 1.13 through 1.15, after getting a begging letter from a certain

Backport 1.13 through 1.15, after getting a begging letter from a certain
BDFL <wink>

  The fullmodname() function chopped off the first character if the
  module existed in the current directory.

  Open results files, which contain binary pickles, in binary mode.
  Remove fallback code that tries to read marshal data from a results
  file, since this module never writes marshal data.