[SDL 0240] WebEngine support for SDL JavaScript

[theresalech]

Proposal: WebEngine support for SDL JavaScript

This proposal is adding a new transport to the SDL JavaScript library to support (progressive) web apps to run on a WebEngine or a browser.

Review: smartdevicelink/sdl_evolution#767

Steering Committee Decision:

The Steering Committee voted to accept this proposal with the following revisions:

• When formatting locales in the manifest.json file, use standard (RFC 5646), and convert locale strings when necessary.
• Do not specify the location of the manifest's <script> tag placement within the proposal.
• All revisions included in this PR: https://github.com/smartdevicelink/sdl_evolution/pull/888/files

The proposal .md file was updated to reflect these revisions on 12/19/19.

[theresalech]

Proposal markdown file has been updated per the revisions included in accepted Evolution Proposal SDL 0240 Revisions - WebEngine support for SDL JavaScript. These revisions change the appID parameter within GetAppProperties to policyAppID and add a minlength of 1 to the param. Please see the proposal markdown file for more details.