Added multiselect to ListView

[ajmeese7]

Adds some additional functionality to the existing #33, which is meant to close out #32.

This implementation has more feature-parity with typical desktop file manager applications in that the ctrl and shift keys now have separate useful functionality. The ctrl key allows for the selection of multiple individual files, whereas the shift key allows for a selection of a range of files.

[ajmeese7]

Do you want changes to be made to try to satisfy the CodeClimate CI?

[andersevenrud]

Do you want changes to be made to try to satisfy the CodeClimate CI?

Don't really have to worry about those unless you're met with a bunch of 'em. But you can look at it if you want to.

[ajmeese7]

In this case I don't believe the changes are necessary, the "complexity" really isn't all that complex in my opinion. Is there anything else you want to see out of this PR?

[andersevenrud]

I haven't found the time to test this myself, but from a code standpoint, this looks OK to me.

I could publish this with a @next tag on npm if you want. I wanna test this myself, but don't think I really have enough time to thoroughly do it until Thu/Fri.

[andersevenrud]

I could publish this with a @next tag on npm if you want

I went ahead and did that. So 4.2.0-rc1 is tagged with next so that it's not picked up by npm updates.

[ajmeese7]

Sounds good, when you manually test please let me know if you encounter any issues and I would be happy to open another PR to fix them.

Additional note, this should close out #32 and #33 now that it is merged.

[andersevenrud]

I'd hold up closing related issued until it's published into current.