Validate API Proposal with JSLint

[anssiko]

Proposed changes:

• Replace unexpected characters '“' with '"'.
• Use 'function (...)', not '(...) =>' when arrow functions become too complex.
• Remove unexpected trailing spaces.
• Wrap placeholder "..." arguments into comment blocks.
• Make "peer.accept() / peer.reject();" valid by commenting out the alternative.

Ignored:

• Break lines longer than 80 characters.
• Empty block warnings.

JSLint is strict but often has reasonable proposals.

[ibelem]

Thanks @anssiko for the detailed linting fix, merged this PR.