various fixes to darcs conversion script 1. removed files were missed 2. hidden files in top directory were not added/removed correctly 3. suppressed spurious warning on adding new files. 4. hg changeset now checked in with original author and date 5. __file__ not supported by pdb.py

abort: Failed to parse .../t/.hg/hgrc
File contains no section headers.
file: .../t/.hg/hgrc, line: 1
'invalid\n'