Development

[rianbotha]

Please check if the PR fulfills these requirements

• [x] The commit(s) message(s) follows our guidelines - I found this a bit complicated, but I think I meet the minimum requirements
• [x] Tests for the changes have been added (for bug fixes / features)
• [x] Docs have been added / updated (for bug fixes / features) - I don't think any doc change is required

What is the current behavior? (You can also link to an open issue here) When startOpen is true the drawer does not show since the hiddenOverlay and hiddenDrawer states are also set to true.

What is the new behavior? hiddenOverlay and hiddenDrawer are set to the inverse of startOpen, which means that the drawer is visible when startOpen is set to true

Does this PR introduce a breaking change?

• [ ] Yes
• [x] No

If this PR contains a breaking change, please describe the impact and migration path for existing applications: ...

Other information: