Converted `at_chat_bg.png` to 8-bit input depth.
Fixes CocoaPods error on `pod spec lint`:
`- NOTE  | [iOS] [xcodebuild]  libpng warning: Warning: Input PNG does not have an 8 bit input depth.  Please convert your PNG to 8-bit for optimal performance on iPhone OS.`
Fixes IOS-637
iOS 8 fix/hack for rotating the Message Panel.
Should replace with an Auto Layout view.
Fix/hack for horizontal presentation of Message Panel in iOS 8.
Hack/fix for iOS 8 issue where frame's animation is offset from (0, 0) origin when animation starts from landscape.
Will soon convert Message Panel to use Auto Layout.
Add tests for `person` and `device` custom data in criteria.
Remove tests checking if `custom_data` key is present.
Custom data is being held over from 3ceeba3ef42a5832280ce3abd3962a3292f9ef54 and failing.
Add `person` and `device` keys in correct format: "device/custom_data/abc_xyz".
We were formerly adding custom data as a dictionary under key "device/custom_data", which did not correspond to keys from the server and allow matching in the criteria predicate.
Fixes IOS-647
Skip potential criteria targeting of the `integration_config` keys, rather than add each individually as `device/integration_config/config_name`.
Merge pull request #128 from apptentive/customDataCriteria

IOS-647 Fix Custom Data targeting in criteria
Merge pull request #129 from apptentive/iOS8

Additional fixes for iOS 8
Added additional logging to help dev when an interaction has not been downloaded or is not shown.
Merge pull request #130 from apptentive/dev2

Added additional logging to help dev when an interaction...
Update to version 1.5.8
Merge branch 'master_apptentive'