Custom Component Support

[RobbieTheWagner]

Inspector currently doesn't do a great job of supporting custom components, tagless components, etc. This issue should serve as a place for us to discuss how we want to support everything, how it should look, and how we get one nice cohesive experience for all the things.

[RobbieTheWagner]

@rwjblue any updates on what we want to do here?

[nummi]

Template-only component:

{{template-only-component}} based on filename?

---

Component used with angle bracket syntax:

<AngleBracketTest>

[nummi]

There are many ways a component can be used in a template — do we want to support them all? I would say yes, we want to mirror what the developer typed.

[chancancode]

Should be fixed by #1088 in the next release.