Revert incorrect commit 9351edad48523bb38b1bf651506786bdc8814f62, which broke file type detection
in chpathtool.py with Python 3 and magic module present.

>>> import magic
>>> m = magic.open(magic.MIME_TYPE)
>>> m.load()
0
>>> m.file(b"/etc/fstab")
'text/plain'
>>> m.file(str(b"/etc/fstab"))
"cannot open `b'/etc/fstab'' (No such file or directory)"
Follow-up to commit 96ded9cff423d773ee31a696a691dd6610c315b7: Restore "/" characters.
localization: properly decode formatted number for localized_size().

Fixes: https://bugs.gentoo.org/show_bug.cgi?id=519124
repoman: fix atom.blocker checks.

The original checks assume that no-blocker is denoted as 'None'.
However, currently atom.blocker returns just 'False'.