convert_git: avoid returning two entries for the same file in getchanges
This could happen in merge changesets if the merged file was different
from both parents.
#!/bin/shhg initecho This is file a1 > ahg add ahg commit -m "commit #0" -d "1000000 0"touch bhg add brm bhg commit -A -m"comment #1" -d "1000000 0"