IE11 Fix

[joer80]

I got an error in IE11 and fixed it by changing:

var Vue2Filters = {
install(Vue) {

to:

var Vue2Filters = {
install: function(Vue) {

Just wanted to let you know!

[autobrain-stanley]

Yes it seems this lib isn't transpiled with es2015 transforms so we aren't getting the transformed version of method property short hand