Weboob was renamed to Woob

Weboob was renamed to Woob with its new 3.0 release: https://woob.tech/news

We need to update our code and also make it backwards compatible. Note that the renaming happened for ethical reasons, and we should make every effort to remove any trace of the old, offensive name from our code.

TODO:

• Refactor the code, replace all occurrences of Weboob with Woob
• Ideally try getting the code work with Weboob/Woob < 3.0
  • Apart from Arch and Ubuntu (<= 18.04), almost no other popular distributions shipps weboob, according to repology
  • thus most would use pip/pip3 to install it, which already provides the updated woob package
  • I am not even sure "weboob/woob" is designed to maintain any kind of backwards compatibility, given that the modules are downloaded directly from their repositories, bleeding-edge, upon configuration
  • as such I don't see a need to maintain backwards compatibility with it
• Decide what to do with the KParts plugin name: should we keep the old kmymoney-plugins-weboob name or rename to kmymoney-plugins-woob?
  • What would the consequences of renaming the plugin be?
    • Loosing account mappings? No. We use name-agnostic wb-id and wb-backend values to map to woob/weboob accounts.
    • Loosing plugin settings? No, there aren't any.
    • We'd end up enabling the woob plugin even if weboob was previously disabled by a user
• Check provider key for any opened book file file and update it from weboob to woob if needed