Fix license headers in BitcoinURI/BitcoinURIParseException
Fix question marks could not be used in payment protocol request URI. Removes the check for multiple question marks in the bitcoin URI.

Also see https://github.com/schildbach/bitcoin-wallet/issues/169
WalletTool: magic --output value ALL for easier emptying of wallets.
pom.xml update to exclude untestable classes from coverage report
Adds Wallet tests, extracts FooWalletExtension for testing.