Exported Resizer DIRECTION_* and POSITION_* constants

[WebsiteDeveloper]

Fix for #3271.

[jbalsas]

@WebsiteDeveloper Changes look good. I just have one concern. If you dig inside Resizer, you'll see that POSITION_BOTTOM and POSITION_LEFT aren't actually implemented (there's currently no use case in Brackets for them).

We probably shouldn't expose them yet, or if we do, we'd probably want to add an error log in makeResizable to warn that this won't work. Of course, a third option is to go ahead and implement it ;)

@redmunds I think you reviewed this back in the day... what do you think?

[redmunds]

I agree that things that have not yet been implemented should not be exposed.

[WebsiteDeveloper]

i'll just remove the exports for those and if i have time i'll look at implementing them, and then reexporting ;)

[jbalsas]

Looks good! Merging