Merge pull request #109 from apptentive/french_canadian

Add French Canadian string  resources.
Revert "Add French Canadian string  resources."
Merge pull request #111 from apptentive/revert-109-french_canadian

Revert "Add French Canadian string  resources."
Added methods for engaging events with `customData` and `extendedData`.
Added methods for sending Metrics with with `customData` and `extendedData`.
Store `data`, `customData`, and `extendedData` in the Event dictionary that formerly held `data`.
Store each under the correct key for server when adding to the dictionary, rather than later in `apiJSON`.
Added convenience methods for creating the initial `extendedData` types.
Added demo event with `customData` and `extendedData` to FeedbackDemo.
Added logging of 422 errors when `customData` or `extendedData` is malformed.
IOS-585
Not including `extendedData` keys if value passed in is `nil`.
Merge commit '3dde5f7b70545bd51533199347fcc1d754f4dec5'
Merge branch 'extendedData'