Fix the display of inline arglist

[zyd-n]

This fixes up the display of the inline arglist for Lisp (Slime and Sly) via the C-2 keybinding. Before, symbols would be very cluttered with unnecessary package prefixes and were not aware of package local nicknames. You would also get an error if you tried to get the arglist for a macro. Tested on both Sly and Slime but the patch probably needs some style review as I don't write a ton of elisp.

Before:

After:

Here is a package local nickname defined in my current package being successfully displayed:

And here is a package local nickname but it's a nickname not defined in my package but a different home package:

[enzuru]

Looks good, I'll cleanup style in a followup commit.

[enzuru]

Sorry, I think I merged this too soon. I began to run into a bug with C-2:

"upcase: Wrong type argument: stringp, nil [9 times]"

Reverted for now.

[zyd-n]

@enzuru

Sorry, I think I merged this too soon. I began to run into a bug with C-2:

"upcase: Wrong type argument: stringp, nil [9 times]"

Reverted for now.

Are you getting this in sly or slime? I've been using this patch for a while and haven't seen that yet.

[enzuru]

Sly!