Fixes #1193, #1350, #967: Fixes daw bugs

[Chillee]

As I was working on the "aw" object, I thought I would fix the other related bugs.

It'd be ideal if I didn't need to special case this, but from thinking about it, it does seem like it's a special case. Normally, when you daw with a "." right at the end, you also want to delete all the whitespace on the left of the word until you reach another word. In this scenario, however, you want it to stay in the same place.

I was working on a complete rewrite of the 'aw' object based off "boundaries", but decided that it was overengineering. However, while writing it, I came some more cases where our behavior doesn't align with vim. I'd like some feedback on whether those cases are worth fixing (imo, vim does some very bizarre things in some of these cases).

one  
|  
three

becomes
|one

[xconverge]

does this also handle this test:

  newTest({
      title: "Can handle 'daW' around word at end of line",
      start: ['one t|wo',
              ' three'],
      keysPressed: 'daW',
      end: ['on|e',
            ' three']
    });

This PR looks great! Thanks!

[Chillee]

I've only touched the "aw" (lowercase) object, but as the test case for "aW" you posted is the same as the one for "aw" I fixed, I imagine the fix should be similar.

I'll check it out.

[xconverge]

Want me to merge this and make that a separate issue?

[Chillee]

Nah I'm almost done with the bug fix.

[Chillee]

Actually, could you? I found some other bugs with "aW" that seem to be a bit harder to fix. Namely, tests like

one |two

result in everything being deleted.

I can make the new issue(s).

I'm actually surprised nobody has reported these bugs. I guess people don't really use the "aW" object much?