feature/clear text with delegate: jmoody additions

[jmoody]

Motivation

Merging this PR will update #382

• Fixes Objective-C naming convention in ClearText route
• Fixes indentation and spacing
• Adds TODO about handling target/action pairs
• Adds Cucumber tests for GET clearText and POST setText (on webviews)

Notes

To the keep the diff manageable, the DeviceAgent TestApp binaries will be pushed to develop once #382 is merged.

[jmoody]

@jescriba You might be interested in the diff and the tests.