- Use different Metadata objects to write and read a PKG-INFO (METADATA)
  file, to make sure the tested values come from the file

- No need to restore methods on an instance after monkey-patching them:
  the methods are still the same on the class

- Harmonize dedent calls

The two public functions in database default to sys.path if the given
*paths* argument is None; the private functions don’t have default
values for their arguments anymore, which is fine as the public
functions that call them pass their arguments down.  Likewise in
install, the functions will pass down their *paths* arguments down to
database functions.

A one-line unneeded function in install was removed instead of being
changed, and the few remaining tests that used brute-force restoration
of sys.path have been cleaned up to use sys.path.remove.

Now only the compatibility layer (in create, util and install) talk
about setup.py.

Don't modify mutable default arguments...

After 1a3e8db28d49, Windows XP could not os.stat at all due to raising
immediately when GetFinalPathNameByHandle wasn't available (pre-Vista).
The proper behavior in that situation is to just not attempt a traversal
rather than outright rejecting.

This change additionally handles a failed malloc by setting the error code
and returning false.

Patch by Hirokazu Yamamoto.

Use of DeviceIoControl to obtain the symlink path via the reparse tag was
removed. The code now uses GetFinalPathNameByHandle in the case of a
symbolic link and works properly given the added test which creates a symbolic
link and calls os.stat on it from multiple locations.

Victor Stinner also noticed an issue with os.lstat following the os.stat
code path when being passed bytes. The posix_lstat function was adjusted to
properly hook up win32_lstat instead of the previous STAT macro (win32_stat).

Spawn a new process instead of using fork(). Patch written by Charles-François
Natali.

This allows findsource() to work in doctests.

A patch from Dirkjan Ochtman.

methods.