PR: Remove Kite completion provider code

[jsbautista]

Description of Changes

Remove kite from the Spyder main repository

Related to spyder-ide/kite-provider#1

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@jsbautista

[dalthviz]

Thanks for the work here @jsbautista ! I left a comment regarding another entry to remove from the NOTICE.txt related with pybloom_pyqt utils code (which also is missing to be removed).

Besides that, I think we need to update the docstrings/comments for the completions plugin at:

• https://github.com/jsbautista/spyder/blob/f79aafd044be814db8b77985188d8c15fb8a59e7/spyder/plugins/completion/plugin.py#L67 (remove kite mention)
• https://github.com/jsbautista/spyder/blob/f79aafd044be814db8b77985188d8c15fb8a59e7/spyder/plugins/completion/plugin.py#L1234 (remove kite mention and just put providers in general)

Also, I'm not totally sure what we should do with the entry point validation for Kite at https://github.com/jsbautista/spyder/blob/f79aafd044be814db8b77985188d8c15fb8a59e7/spyder/plugins/completion/plugin.py#L239-L244

What do you think about that last point @ccordoba12 ? Should we keep the entry point validation for Kite?

[dalthviz]

Thanks @jsbautista ! I did a small suggestion for text inside a comment and I think the only missing element to check is what to do about the entry point validation for Kite at https://github.com/jsbautista/spyder/blob/f79aafd044be814db8b77985188d8c15fb8a59e7/spyder/plugins/completion/plugin.py#L239-L244

What do you think about that @ccordoba12 ?

Other than that this LGTM 👍

[ccordoba12]

At first glance, this looks good to me. Thanks @jsbautista for your work on it!

The only thing missing is to allow the external Kite code completion plugin to be loaded in Spyder. I don't remember where that's forbidden right now, but you can take a look at it with @dalthviz.

[ccordoba12]

Thanks @jsbautista and @dalthviz for your work on this!