Fix build for Xcode6, iOS8

  - Add $(inherited) flag to OTHER_LINKER_FLAGS
  - Update to Kiwi 2.3, fixes Cocoapods XCTest import error
Xcode6 auto-generated Storyboard updates
Customize link button color with linkColor key in settings.plist

  - Defaults to secondaryTextColor
  - Sets candidate details text description to be primaryTextColor