With multiple selects, cannot select options with keyboard after using mouse to select options

[pvictor]

Hello,

Problem: With multiple="true" we can select option with keyboard, but if we click on an option with mouse, then selection with keyboard doesn't work anymore.

Tested with bootstrap-select-1.13.17 on Chrome and Firefox.

Here a playground: https://plnkr.co/edit/u7ohgCl2jVWxDy1B

To reproduce:

• open picker
• keyboard: type "a" then enter -> "A" is selected
• keyboard: type "b" then enter -> "B" is selected
• mouse: click on any option -> selected
• keyboard: can't select an option (except if picker is closed and reopened)

Thanks for your work!

[caseyjhol]

Introduced by the fix for #663.

[caseyjhol]

Released in v1.13.18!