[FIX] leftover of commit 790312dbf92e302f40782a60c5dc208cd6877079wq
[IMP] website_twitter: authentication error popup with proper description based on twitter error codes and responses

[CLEAN] website_twitter: some linting in twitter_config.py file (indentation
errors, imports to remove, spacing issues).
[IMP] membership: usability

- new help tip when there are no members
- allow to search for members and tags
- move reporting to "Reporting" menu