Add GUI to Wolfram Alpha

Description

The primary purpose of this PR is to add a GUI to Wolfram Alpha.

Doing this included a relatively big refactor including:

Removal of 3rd party wolfram alpha package instead querying the API endpoints directly.
Consolidation of the two API clients into 1. If an API Key is supplied the Wolfram endpoints will be queried directly, otherwise Mycroft's backend will be used.
Consistent CQS approach to new Wikipedia and DDG Skills using a named Tuple to store last query.
Consistent UI qml as used in Wikipedia and DDG.
It currently has 3 possible types of display:
1. Equations - eg "what is 2 + 2" will display: "2 + 2 = 4"
2. Conversions - eg "how many teaspoons in a tablespoon" will display: "3 tsp"
3. Most other things - eg "who is the current president of the USA" will display "Joe Biden" with an image.
presently the first 2 GUI's are very limited and just show text but these can be expanded over time to show more detailed visuals representing the answer.
Images for type 3 are sourced directly from the Wolfram answer where possible. Else if a Wikipedia image is mentioned we grab that. Else we do a DuckDuckGo image search and return the first result.

An issue has been created on Common Query to bring consistency to the various Common QA fallbacks and the functionality they present to the user.

Type of PR

[x] Feature implementation
[x] Refactor of code (without functional changes)

Testing

The new Wolfram Alpha endpoint is not yet available in Mycrofts production backend. You must first pair your device against account.mycroft-test.net eg

mv ~/.config/mycroft/identity/identity2.json ~/.config/mycroft/identity/identity2.json.bak
mycroft-config set server.url "https://api.mycroft-test.net"
mycroft-start restart all

or add your own Wolfram appID to settings.json.

VK tests are handled by Common Query.

CLA

[x] Yes

MycroftAI / fallback-wolfram-alpha