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]

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[creaven]

issue is still actual