clfilter: stronger detection of filtered changeset in changectx.__init__ We previously let some IndexError spill out of this function. A new tests is added to check the command that spotted the error.

validate: check for spurious incoming filelog entries Accepting those will lead to "mild corruption", correctly reported as an error by hg verify, but often not a problem in practice. Enabled when server.validate is switched on.

zsh_completion: add descriptive branch names to head revisions