Add help text on hover

[ghost]

Is your feature request related to a problem? Please describe.
VS Code supports showing help text on hover. e.g. in Python, it shows the docstring of the function.

Describe the solution you'd like
Currently, help text is shown while typing a function name in the load script:

Similar help could be shown when a function is clicked or hovered, such as in this Python example:

Additional context
I think this might be related to Programmatic Language Features, specifically Hover Request.

[konne]

Hi, thx for this feature request.

@r-hannuschka we have all this text information's available through the project qlik-engineapi and this should be easy after we have introduced a language server what we also need for #324

@DAVIDWALES this will have at the moment a lower prio