replaces the threads in the Node class with a single scheduler executor service
initiates the refactoring and redesign of solidification in TransactionValidator.java
While milestone solidfication/network propagation is still far from optimal, this PR still should be able to eventually solidify and propagate all the transactions
This PR:
While milestone solidfication/network propagation is still far from optimal, this PR still should be able to eventually solidify and propagate all the transactions