improve: create missing RendererFunc error message

[13rac1]

Improve the development debugging process by better handling a
missing Node Kind RendererFunc. This:

panic: runtime error: index out of range [22] with length 20

Becomes:

panic: RendererFunc not found for kind: KindName

[13rac1]

@yuin Is there any issue with this change? It's been sitting a month now.

[13rac1]

Bumping to avoid Bot closure.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[13rac1]

@Stale No.

[yuin]

Same PR was submitted before: #107.
If I merge this kind of PR, I prioritize older PR over this.

[13rac1]

In #107 (comment)

This kind of PR has been submitted before.
Works as intended. This is coding problem so it should panic.

I agree, it should panic, which is why my implementation continues to do so, but the message is now useful/helpful and not incorrect/misleading for the developer.

If I merge this kind of PR, I prioritize older PR over this.

Okay, can we merge #110 ? The fact @abhinav, someone else, and myself have all attempted to correct this developer experience speaks to the frustration encountered.