Title, Boilerplate, Clean-up

I propose the following clean-ups to the spec. If there's no disagreement,
I'll update the spec with these tomorrow.

Title
- Change name from "Speech JavaScript API Specification" to "Web Speech API
Specification"

Copyright and Boilerplate
- Update Copyright and Boilerplate per W3C CG report requirements:
http://www.w3.org/community/reports/reqs/
- Add line: "Please refer to the errata for this document, which may
include some normative corrections." which links to an empty, placeholder
document.

Abstract / Introduction (This section is non-normative)
- Move the second paragraph in the Abstract to the Introduction.
(Referencing the "Incubator Group Final Report" both places is redundant
and confusing.)

Section 3 Use Cases (This section is non-normative)
- Move "Temporal Structure of Synthesis to Provide Visual Feedback" from
unsupported list to supported list.

References
- Update WebIDL to point to latest version: http://www.w3.org/TR/WebIDL/

Glen Shires