Prevent open firing

[jbandelin]

Prevent the open function from running when pinny is already open.

Status: Ready for review

Reviewers: @donnielrt @scalvert

Changes

• Check for open class on pinny element before running open function
• Add event test to confirm only one open event is fired when pinny is opened twice

  How to test-drive this PR

• checkout this branch
• grunt test
• grunt serve
• view pinny example page and open inspector
• attempt to open one of the example pinnys twice without closing it
• opening animations should only execute once

[donnielrt]

Good stuff, I'll take this for a spin!

[scalvert]

This looks great, @jnurse!

I added a corresponding check inside close, so we have consistency between the two.

[scalvert]

:+1: