Expose monaco IDE settings to end user

[dsmmcken]

IDE preferences are complicated. Monaco has good defaults, but for users to really feel at home, they may want to customize monaco to behave more like their preferred IDE. This was spurred by a complaint from @jcferretti around acceptSuggestionOnEnter conflicting with wanting to use enter strictly for newlines.

Expose the options (or some reasonable subset) from https://microsoft.github.io/monaco-editor/api/interfaces/monaco.editor.ieditoroptions.html to the end user (assuming there is an easy way to gather enum options). These options should be presented similar to shortcut key customizations, in an adjecent settings section, with drop downs for the enums.

[rcaudy]

I think we should go with a default (false) that isn’t ambiguous, and that doesn't let autocomplete break perfectly correct code you typed and want to submit. Submitting something other than you intended can have real world consequences in our REPL, it’s not really an IDE.

[mofojed]

Would also be nice to list the shortcuts that are available in Monaco.