See merge request nexedi/slapos.core!222

See merge request nexedi/slapos.core!240

This reverts commit 7e49ec5e.

This reverts commit febcf1b4.

See merge request nexedi/slapos.core!239

See merge request nexedi/slapos.core!185

See merge request nexedi/slapos.core!236

We observe that software sometimes fail due to transiant errors such as
DNS/network errors, so increase the default number of retries to build
software from 2 to 10.

Sometimes also instance is failing for monitoring or other errors that
might become OK if we retry more, so increase the default number of
retries for instance from 10 to 20.

  It was added as "0" in order to run first, as the later tests calls logout and can be started as anonymous.

Files on the partition can be created with mode disallowing removal, so use
slapos.util.rmtree to ensure they will get removed instead of failing.

In some cases partitions can chmod -w some paths, so use util.rmtree to
overcome this situation.

   ... rather them the user's language

   Payment mode is set on the payment object and invoice

    Also inform payment_mode to let the script handle the display of information

  * erp5_immobilisation is now installed
  * "Update translation table" is verbosed as some bt5 are always marked to be resinstalled

    Use Wechat payment rather them payzen

Also change places where xml_marshaller were used directly to always use
the wrapper from utils (except in tests for simplicity)

On python3, deleting a chmoded folder causes this error:

    Traceback (most recent call last):
      File "/usr/lib/python3.7/shutil.py", line 423, in _rmtree_safe_fd
        dirfd = os.open(entry.name, os.O_RDONLY, dir_fd=topfd)
    PermissionError: [Errno 13] Permission denied: 'directory'

    During handling of the above exception, another exception occurred:

    Traceback (most recent call last):
      File "slapos.core/slapos/grid/slapgrid.py", line 607, in processSoftwareReleaseList
        software.destroy()
      File "slapos.core/slapos/grid/SlapObject.py", line 360, in destroy
        rmtree(self.software_path)
      File "slapos.core/slapos/util.py", line 267, in rmtree
        shutil.rmtree(path, onerror=chmod_retry)
      File "/usr/lib/python3.7/shutil.py", line 491, in rmtree
        _rmtree_safe_fd(fd, path, onerror)
      File "/usr/lib/python3.7/shutil.py", line 425, in _rmtree_safe_fd
        onerror(os.open, fullname, sys.exc_info())
      File "slapos.core/slapos/util.py", line 264, in chmod_retry
        func(failed_path)
    TypeError: open() missing required argument 'flags' (pos 2)

Our error handler was assuming that on python 3 the EACCESS for the
directory would happen first on an os.lstat call [1], which is true when the
top level folder is not listable, but it did not support the case where
the top level folder is listable but contain another folder that is not listable.
In that case, the first error is an os.open [2]

Tests from erp5.util (where this function came from) only covered the 1 case but
new tests in slapos.core covered the 2.

Anyway, do the "chmod folder and retry from beginning" for both 1 or 2 cases.

[1]: https://github.com/python/cpython/blob/3.6/Lib/shutil.py#L475

[2]: https://github.com/python/cpython/blob/3.6/Lib/shutil.py#L418