Update content.json

Have updated CTAs for Sharing, Collaborating, Community, Privacy and Open Practices as per bug 1027264. Only part I wasn't sure about was the # of brackets on the bottom. Originally had 5, now has 4.
Update content.json

Updated kit authors + descriptions under "webit-design" section and added the Mobile Design Kit.
1.1.13
Merge pull request #821 from keyboardkat/patch-1

Update content.json
Merge pull request #831 from keyboardkat/patch-2

Update content.json