feat(vue): allow to change global/inject route name

[iamandrewluca]

Closes #796

[bakerkretzmar]

Thanks a lot for the PR and the detailed issue! We're going to pass on adding this to the plugin for now, it's really just a convenience and we want to keep it super simple. If you want to rename the helper you should create the mixin/provider yourself just like you demonstrated in #796, instead of using Ziggy's included Vue plugin. That way is also less code and gives you complete control over the implementation.