Provide documentation about using custom components

[ikoevska]

From Vladimir Amiorkov via email:

There are zero documentation/blogs about this topic. I did not found anything that provides information how the nativescript-vue elementRegister works.
Suggestion: We would write some help articles on this topic because if we want the community to be able to write support for nativescript-vue in their plugins we have to make it as easy as possible with good reading meterial

More:

I was expecting at least a very simple example that shows how to register an element, and register a custom component that the nativescript-vue will render. An example that showcases the lifecycle events of VueJs inside the NativeScript framework or at least links to the official VueJS documentation on the “custom component” topic
Suggestion: I think we need to have an separate article in the documentation about this topic. This will make the plugin developers have a place to start from. As a bigger task I see an entire section of the documentation dedicated to how a custom component/directive should be implemented in the nativescript-vue realm or even a section about “ How to use custom {N} plugins inside NativeScript-Vue”

Tasks:

• Create docs about creating vue-compatible plugins. In particular, cover how nativescript-vue-elementRegister works.
• Create docs about using custom plugins/components in {N} Vue.