Fix for demandimport.py and Windows compiled version.
From Shun-ichi Goto in BTS issue 457 http://www.selenic.com/mercurial/bts/msg2780
adding he
llo
abort: '\n' and '\r' disallowed in filenames
adding he
llo
abort: '\n' and '\r' disallowed in filenames
adding hell
o
abort: '\n' and '\r' disallowed in filenames
adding hell
o
abort: '\n' and '\r' disallowed in filenames
f he
llo he
llo
f hell
o hell
o