hooks: add preupdate and update hooks.
preupdate run before working dir updated. can prevent update.
update run after working dir updated.
(the addremove command is deprecated; use add and remove --after instead)
adding foo
(the addremove command is deprecated; use add and remove --after instead)
adding bomb
adding a.c
adding dir/a.o
adding dir/b.o
! a.c
! dir/a.o
! dir/b.o
? .hgignore
a.c: unsupported file type (type is fifo)
! a.c
# test absolute path through symlink outside repo
A f
# try symlink outside repo to file inside
abort: ../z not under root