Update content.json

Within CodingScripting blob: 
* made grammatical edits on lines 1158-1170
* added youtube embed to line 1142
* fixed incorrect Javascript takeover URL on line 1201
* added two new resources to "teach" section
Merge pull request #950 from keyboardkat/patch-20

Bug 1046309 - Web Literacies Map: Add new teaching kits to "Coding/Scripting" page in JSON