Update Chef dependency to Chef 11

Also add dependency on json <= 1.7.7, required by Chef 11.

Resolves problem: Bundler could not find compatible versions for gem
"json" (required for chef and berkshelf).

Partial fix for bug #1183540

Change-Id: Ia10a0256b782eafe70363e737f4f79ce2bb8be82
Merge "Update Chef dependency to Chef 11"