[2.x] Move Jetstream components to Components directory

[jessarcher]

This PR renames the resources/js/Jetstream directory to resources/js/Components.

This signals to the user that the components belong to them and can be used outside the Jetstream pages and customized as needed. I've seen repos where people create their own Components directory and maintain two sets of buttons, etc.

This is also consistent with Breeze.

[joelbutcher]

@jessarcher Would it also be worth renaming the imports of these components to equally detach the perceived ownership from Jetstream? e.g import JetButton from '@/components/Button.vue to import Button from '@/components/Button.Vue?

[jessarcher]

@joelbutcher I'd love to, but the Vue style guide says not to.

Yesterday I asked Evan You whether he'd still advocate against it and this was his response:

Not as strictly, but I’d still avoid names that overlap with known native elements.

So for components like Modal I think we should be fine. For things like Button, maybe we figure out some more descriptive prefixes for them. E.g. PrimaryButton, SecondaryButton. Input and Label might be TextInput and InputLabel or something.