Major Revision of iOS SDK

[hactar]

So I've rewritten many parts of the SDK while maintaining API compatibility with the previous SDK version (4.1.0). It's what I use for https://subzero.eu/wave/

Features

• ULaw Compression Support: On LTE and WiFi, the SDK continues to use uncompressed PCM, but on 3G and below the SDK now uses ULaw compression, which majorly increases speed (x2-3) on slow connections (sound quality loss appears not to affect recognition quality in my tests)
• WitMicButton Color: WitMicButton now respects tintColor property, so you can color it to match the app (used to be #48)
• Uploads Fixed: The old uploader did not enqueue chunks after the stop button was pressed, this fixes this issue
• Recorder Buffer Enqueue Fixed: This solves issue #54
• Fixed Tests: The old tests were completely broken, this now has one working test using XCTest, its not much but can get people started for more tests now. Solves #10, #13
• VadTracker: The VadTracker was broken (sent errors if the user manually stopped recording) so calls to it have been removed. Solves issue #59
• Delegate Callback Order: The record stopping and did grasp intent callbacks were being called in a different order depending on if there was an error or not, this has been fixed.
• Pull Request #68: Includes and improves this pull request (retain cycles, install warnings). This fork now really does cleanly work and install without warnings for new people downloading it.
• Quieter: Less NSLog, more debug.

  Caveats

There are a few changes I made that might not make everyone happy:

• iOS 7.0 and above: Previous was 6.0, but the CoreTelephony stuff for connection speed detection is only available in iOS 7. iOS 7,8,9 has a very high adoption rate anyway.
• Pod dependency on GCNetworkReachability: Needed for connection speed detection.
• Context Setter no longer sets user location: I don't know why the SDK did this as it's a privacy issue - if the developer wants to share the location of the user with wit then this should be optional and not "default on" in my opinion. I have had no issues with running the SDK without setting this context.

  Issues

• WitTests contain access token: I needed to provide an access token and setup for the network test so I provided a client token - if this is an issue then the token needs to be removed and blocked. Maybe an official "testing" token could be created.

[thediary]

Let's please get this merged into the main branch of the SDK! There are so many great improvements in here, and after testing some of them in our app, I think they would be a welcome addition into the main library.

[spencerp]

Looking great! Thanks for making these changes! Most of the comments are nits. The only things I really care about are: 1) Making location sharing in the context default off, but configurable. 2) Double-checking the project settings to make sure all of the changes were intentional

[hactar]

@SpencerP: Thanks for the thorough code check, always glad when there's more pair of eyes on code :) regarding your comments 1) location sharing: While I agree that making it optional would be a nice solution, its not enough to simply make the calls optional, as the current code isn't very clean:

• it never calls stopMonitoringSignificantLocationChanges
• it doesn't consider the case when locationManager.location is nil and just sets lat and long to 0
• it actively calls requestWhenInUseAuthorization instead of passively just filling in data if its available (context location is optional in wit, not required). This is what tripped me up as a user complained why I was asking for his location when he had asked where the "eifel tower" is - a query which clearly does not need the user's location. This is where I noticed the sdk was doing this at all.

So until someone rewrites this code (I'll happily accept a PR to my PR:)) I humbly propose that not having it in is better than having this version of the code in.

2) I looked over the project settings again and to me they appear fine, but honestly I'm not an expert on all Xcode project settings. The changes come from:

• Moving the deployment target to 7.0
• Hitting the "validate settings" button in Xcode
• Adding the XCTest

[spencerp]

Sounds good! I'll see about refactoring to expose the location option later, but looks like that will be too big a change for this diff.