Add webc:is="template" to webc:type="js"(and render) docs

[okmanideep]

Issue with the current README.md

img.webc in README, doesn't actually render the returned string in the webc:type="js" and webc:type="render" script blocks. Since it is missing webc:is="template"

- <script webc:type="js">
+ <script webc:type="js" webc:is="template">

Figured this out after looking at examples/render/components/img.webc (Thanks to @manekinekko)

Is this really required?

The syntax in the current docs which is not working, actually looks intuitive.

Just like we aren't adding an extra template for normal HTML, we shouldn't need to specify webc:is="template" for the render scripts.

Thoughts?

[zachleat]

HMMMMMMMM. I wrote out a big long response here but I think you’re right and I want to fix this in the library.

Starting in WebC v0.9.0 the following changes will smooth this a bit:

1. [Breaking] webc:type="js" will have an implied webc:is="template" (unless otherwise specified) and an implied webc:nokeep (unless webc:keep specified)
2. [Breaking] Instead of webc:root webc:keep, you must use webc:root="override" instead
3. We’ll also ease up on circular component references when using webc:root in component definitions
4. I also spotted a bug with attribute merging class and style when using webc:root and those attributes do not exist in host component, which also rolled up with this change.

Thank you!