Add default neovim lsp keymaps

[asadzman]

Is your feature request related to a problem? Please describe.
I would like default neovim lsp commands to work ootb. The gr* commands. Context, nvim-lsp-defaults

Describe the solution you'd like
Include the keymaps by default.

Describe alternatives you've considered
I can for now add these keymaps in settings.json.

    { "before": [ "g", "r", "a" ], "commands": [ "editor.action.codeAction" ] },
    { "before": [ "g", "r", "n" ], "commands": [ "editor.action.rename" ] },
    { "before": [ "g", "r", "i" ], "commands": [ "editor.action.goToImplementation" ] },
  //  { "before": [ "g", "r", "x" ], "commands": [ "codelens.showLensesInCurrentLine" ] },
 // Not sure about is there some equivalent "codelens.run()" in vscode
    { "before": [ "g", "r", "r" ], "commands": [ "editor.action.goToReferences" ] },
    { "before": [ "g", "r", "t" ], "commands": [ "editor.action.goToTypeDefinition" ] },

Additional context
n/a