merge: add 'isknown=True' to a dirstate.normalize() in _unknowndirschecker Per the docstring for dirstate.normalize().

merge: pconvert paths in _unknowndirschecker before dirstate-normalizing This fixes the failure in test-pathconflicts-basic.t on Windows. The test was passing in 'a\b', which was getting normalized to 'A\B', which isn't in dirstate. (The filesystem path is all lowercase anyway.) This isn't the only case of calling dirstate.normalize(), but other methods here (util.finddirs()) seem to assume the input paths are already using '/'. I think the backslash comes from wvfs.reljoin() (in this case), but could also come from wvfs.walk(), so this is the only case that needs it.

util: enable deprecation warning for stringutil proxy (API) .. api:: Several generic string helper functions have been moved to utils.stringutil module.

stringutil: bulk-replace call sites to point to new module This might conflict with other patches floating around, sorry.

stringutil: move generic string helpers to new module Per https://phab.mercurial-scm.org/D2903#46738 URL and file paths functions are left since they are big enough to make separate modules.

util: remove unused private constant '_hextochr' The only user, _urlunquote(), was removed by 81d38478fced.

util: mark internal constants of escapedata() as private

util: adjust indent level in wrap()

util: mark MBTextWrapper as private Makes porting slightly easier.

util: add helper to define proxy functions to utils.*