Support passive event listeners

[mark-de-haan]

I'm submitting a ... (check one with "x")

[ ] Bug report => search github for a similar issue or PR before submitting
[x] Feature request
[ ] Other, please describe

Tell about your platform

• flatPickr version : N/A
• Vue.js version : 2.5.2
• Browser name and version : Chrome Version 61.0.3163.100 (Official Build) (64-bit)
• This package version : 4.0.0

Current behavior
I create a form with one or more instances
When the page loads, I get the following message in my console:

flatpickr.js?1b10:579 [Violation] Added non-passive event listener to a scroll-blocking 'wheel' event. Consider marking event handler as 'passive' to make the page more responsive. See https://www.chromestatus.com/feature/5745543795965952

Expected behavior
VueJS now supports @click.passive (vuejs/vue#5132)
I do not want this message

[ankurk91]

You should report this to flatpickr repo instead.
This package has nothing to do with this.