add role="presentation" to tab <li>s to improve accessibility

Refs #13554.
Per https://github.com/paypal/bootstrap-accessibility-plugin/blob/master/README.md#tab-panel
Credit: https://github.com/paypal/bootstrap-accessibility-plugin

[skip sauce]
Add role="tabpanel" to .tab-pane <div>s to improve accessibility

Refs #13554.
Per https://github.com/paypal/bootstrap-accessibility-plugin/blob/master/README.md#tab-panel
Credit: https://github.com/paypal/bootstrap-accessibility-plugin

[skip sauce]
Merge pull request #14086 from twbs/tab-pane-role-tabpanel

Add role="tabpanel" to .tab-pane <div>s to improve accessibility
Merge pull request #14085 from twbs/tab-lis-role-preso

add role="presentation" to tab <li>s to improve accessibility
add role="tabpanel" to .panel-collapse to improve accessibility

Refs #13555.
Per https://github.com/paypal/bootstrap-accessibility-plugin/blob/master/README.md#collapse
Credit: https://github.com/paypal/bootstrap-accessibility-plugin

[skip sauce]
Add role="tablist" & aria-multiselectable="true" to accordion .panel-group to improve accessibility

Refs #13555.
Per https://github.com/paypal/bootstrap-accessibility-plugin/blob/master/README.md#collapse
Credit: https://github.com/paypal/bootstrap-accessibility-plugin

[skip sauce]
Merge pull request #14088 from twbs/panel-collapse-role-tabpanel

add role="tabpanel" to .panel-collapse to improve accessibility
Merge pull request #14089 from twbs/accordion-panel-group-aria-multiselectable

Add role="tablist" & aria-multiselectable="true" to accordion .panel-group