Add ignoredGlobs option to linter

[evetion]

Fixes julia-vscode/julia-vscode#3495
Fixes julia-vscode/julia-vscode#1711
Fixes julia-vscode/julia-vscode#797

Adds the julia.lint.ignoredGlobs option, which takes a list of regex expression. Matching paths will completely ignored by the linter. The default is set to ["\\..*"], which will ignore all hidden (starting with a ., like .git) folders.

I have moved the request_julia_config earlier, so the user configuration (and not the server defaults) are used in load_folder.

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