[Python3] Add packages compatible only with python3 (part 2)

[ngosang]

This is the first PR to make pymedusa compatible with python2 and python3 at the same time.
This PR is the 2nd in [Python3] series. Code still non working in python3.
Main discussion: #4975

You wanna help?

• Test with python2. Everything should work as usual. Especially test strings/series with non ascii characters. Code still non working in python3.

TODO:

• Add folders ext2, lib3 and ext3 into Python PATH. Remove old package folders in GitUpdateManager.clean instead of adding new code. Rework after Fix unable to start Medusa due to configparser ImportError #5145
• Move backported python2 libs (future) to ext2 folder. Check, there is future and futures. Complete list https://github.com/pymedusa/Medusa/blob/develop/ext/readme.md
• Update GitUpdateManager.clean with the new folders.

  Medusa/medusa/version_checker.py

  Line 708 in 1435fcb

  def clean(self):

• Update dependencies/requirements.txt lists https://github.com/pymedusa/Medusa/blob/develop/ext/readme.md https://github.com/pymedusa/Medusa/blob/develop/lib/readme.md
• Add ext3/sgmllib package
• Add ext3/bs4 package (same version as ext/bs4)
• Add ext3/github package (same version as ext/github)
• Update ext3/yaml after Update bencode and PyYAML #5140 is merged.
  Add ext3/yaml package (same version as ext/yaml)
• Remove ext3/httplib2 after Remove unused Python libraries #5091 is merged.
  Add ext3/httplib2 package
• Remove lib3/bencode after Update bencode and PyYAML #5140 is merged.
  Add lib3/bencode package
• Update lib/unrar2. Done in Update lib unrar2 (python2 and python3 supported) #5096
  I updated lib/unrar2 lib for both python2 and python3. Please test it still works in python2.
• Update ext/pythontwitter . Done in Update Twitter notifier #4990
  The ext/pythontwitter package is really old and not compatible with python3. I added 2 new packages in ext3/pythontwitter and ext3/requests_oauthlib. These packages are only used in python3 (because I can't test in python2) but should work with python2 also. Please copy:
  ext3/pythontwitter => ext/pythontwitter (overwrite)
  ext3/requests_oauthlib => ext3/requests_oauthlib

Libraries non compatible with python3 but the code works if you don't use that features (will be fixed in other PRs):

• lib/synchronousdeluge => Replace 'synchronousdeluge' with 'deluge-client' #5097
• lib/rtorrent

Disclaimer:

I'm testing careful with both python2 and python3 interpreters. With python2 you should expect the same functionally than development branch. Python3 is a long term goal, first versions won't be functional or even won't run.

[ngosang]

PR rebased. Removed changes related to unrar2 and twitter as they have been fixed in #5096 and #4990

@sharkykh I think this is ready for review. I didn't change any package for python2, just added new packages for python3 in a different folder. Python2 should work as it does now. Code still non working in python3. The first PR with python3 support is #4982

NOTE: I removed ext/_markupbase package because It's not python3 compatible and I think It's not necessary in python2 neither.

[ngosang]

@sharkykh in the first commit I duplicated the _configure_syspath() code in the test init file. Where we can move the shared code?

[sharkykh]

@sharkykh I did all requested changes. I tested all in py2 & py3
The only remaining thing is the task to update the lib/ext tables in the doc. Could you help?
Current versions for py2 and py3:

• bs4 4.6.3
• github 1.43.1
• yaml 3.13

Remember, after this PR you should keep 2 versions of these packages. #5200

Sorry, I still don't have time to work on the list...

@sharkykh in the first commit I duplicated the _configure_syspath() code in the test init file. Where we can move the shared code?

I don't think you need to go that far. All you have to do is:

sys.path.insert(1, os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))

import medusa

Once you import medusa (or anything from medusa), all the patches are applied.
This is done in: https://github.com/pymedusa/Medusa/blob/develop/medusa/__init__.py
The medusa package usually gets imported in the actual tests anyway.

[ngosang]

@sharkykh Updated PR all DONE!

• Updated PyGithub to v1.43.2 Update dependency PyGithub to v1.43.2 #5200
• I followed your advice in tests init
• Updated lib and ext readme

@p0psicles I saw your changes in #5232 but I think it's not useful. After this PR all packages are compatible with python2 and python3. Even all packages in lib folder. I prefer to show the folders in the table so, when you update github package. You remember to do it in the 2 folders.

[medariox]

The PR LGTM. Great job @ngosang 👍

I believe all reveiw comments have been addressed

[p0psicles]

Creating merge commit, as the commits are just to clean.