revlog: switch findmissing to use ancestor.missingancestors
This also speeds up other commands that use findmissing, like
incoming and merge --preview. With a large linear repository (>400000
commits) and with one incoming changeset, incoming is sped up from
around 4-4.5 seconds to under 3.
@echo off
rem launch hg.exe from parent folder
"%~dp0\..\hg.exe" %*