Reduced log message spam, callback added for when a random transactions are finished

src/main/java/fucoin/actions/join/ActionJoinAnswer.java

...transaction/ActionCommitDistributedCommittedTransfer.java

...transaction/ActionInvokeDistributedCommittedTransfer.java

...tion/ActionPrepareDistributedCommittedTransferAnswer.java

...ain/java/fucoin/configurations/AbstractConfiguration.java

...n/java/fucoin/configurations/MassWalletConfiguration.java

src/main/java/fucoin/wallet/WalletImpl.java