Produces warnings in Swift 3

[mvoccola]

UIImage.swift

• ZAlertView/Pod/Classes/UIImage.swift:51:71: String interpolation produces a debug description for an optional value; did you mean to make this explicit?
• ZAlertView/Pod/Classes/UIImage.swift:55:39: 'FLT_EPSILON' is deprecated: Please use 'Float.ulpOfOne' or '.ulpOfOne'.
• ZAlertView/Pod/Classes/UIImage.swift:104:82: 'M_PI' is deprecated: Please use 'Double.pi' or '.pi' to get the value of correct type and avoid casting.

ZAlertView.swift

• ZAlertView/Pod/Classes/ZAlertView.swift:121:70: Expression implicitly coerced from 'ZAlertView?' to Any