Option to skip auto install

[creaven]

Vue meta now auto installs if there is global window.Vue.

Problem happens when using nuxt and use global window.Vue (it was necessary to integrate with some shared between multiple apps script). Nuxt installs vue-meta with non-default options, but because window.Vue exists, vue-meta auto installs it with default options and Vue.use(Meta, {...}) in nuxt is not working.

To fix it I think vue-meta should support option to skip auto install like setting global window.vueMetaSkipAutoInstall = true before vue-meta script.

[stale[bot]]

Thanks for your contribution to vue-meta! This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. If you would like this issue to remain open:

1. Verify that you can still reproduce the issue in the latest version of vue-meta
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[creaven]

issue is still actual