Update to Polymer.latest

(contributing.md) grammatical changes for clarity

Changed some wording for better grammatical structure.

BEFORE: "This is why we can't accept all submissions."
AFTER: "This is why we can't accept every submission."

BEFORE: "However, we're always open to look at novel ways to solve existing problems."
AFTER: "However, we're always open to looking at novel ways to solve existing problems."

Remove deprecated JSHint options

Also updates code style for the affected file only.

Fixes #1086
Closes #1087

Ampersand.js - extract methods to collection

Browser tests: Flatten loop

Update Vue.js implementation to use latest version & move from labs to first tab

Fixed JSHint error 'Strings must use singlequote'

fix #1071: Olives: Update Olives and Emily to latest 1.x versions

fix #1073 (ampersand demo 404)

index: add node.js section and express gcp backend