If there's insufficient balance (typical error) then InsufficientMoneyException is thrown (checked).
If the SendRequest is bad in some way, like asking to create a spend that would violate the protocol rules, IllegalArgumentException is thrown (unchecked).
Also make VerificationException (and thus ProtocolException+ScriptException) unchecked.
Resolves issue 425.
Backport misc improvements from PayFile.
Refactor the clickable address out into a custom widget.
Use FontAwesome and the wrapper class for icons instead of a custom image.
QRcode support.
The app is not meant to be usable by end users. It is intended to act as a template for people to build custom apps that use contracts. To that end you can get money in, and empty your wallet, but there's no other controls beyond that.
Apps based on this template look professional and have nice animations and visual effects. You can also use this as a way to learn JavaFX.
