Misc py3 c modules

[github at samba.org]

New comment by catalyst-joe-guo on Samba Github repository

https://github.com/samba-team/samba/pull/152#issuecomment-377112622
Comment:
After @noelpower 's new push with more py3 enabled testsuites, autobuild failed with a few more bytes/str related issues. I've fixed the ones I found so far, and a new autobuild is running via gitlab-ci:

https://gitlab.com/catalyst-samba/samba/pipelines/19672350
https://gitlab.com/catalyst-samba/samba/commits/misc_py3_c-modules-joeg-fork-3

 I guess there will still be failures/errors, but we are much closer to the target now!