Allow to multiple open tabs by default in Tabcordion in accordion mode

[wojtekmaj]

Is your feature request related to a problem? Please describe.

I'm using Tabcordion in accordion mode and I would like to open multiple (in my case: all) panels by default.

Describe the solution you'd like

• Change openTab so that it would accept array of indices when mode is specifically set to accordion, OR
• Ditch openTab, introduce open prop to Tab which:
  • In tab mode, would look for first tab that has open flag and have it opened
  • In accordion mode, would look for all panels that have open flag and have them all opened

Describe alternatives you've considered

• Stacking two Tabcordions on top - didn't look great