util: add optional path auditor argument to canonpath
The canonpath function will default to creating its own path auditor,
but in some cases it will be useful to use a specialized auditor,
e.g., one that wont abort if a path lies within a subrepository.
abort: uncommitted local changes
dirty
M foo
% validate update of standalone execute bit change
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
nothing changed
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
0 files updated, 0 files merged, 0 files removed, 0 files unresolved