[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
[IMP] crm: default filter is 'not dead' instead if 'unassigned' and displays an info message in the crm.stage form view. Dead leads should'nt be included in the default view since they can pollute the view over time. Instead, a filter for all leads (except the dead ones) is used by default. A small info message inform the user that the "dead" status is equivalent to setting probabilities to 0 and to fold the stage in kanban for a crm.stage.
[MIG]CRM: Migrated CRM into new API.