Lots of edits to Transaction subclasses to change/remove 'delete'.
Corresponding extra changes to help reset some transaction fields to pre-process
state during orphaning.
Changed Block, GenesisBlock & Synchronizer to save transactions where appropriate.
Added enhanced GET_SIGNATURES_V2 network message to reduce the number of
block signatures sent over network.
Peers are now version 2 if they send a new-style build version string,
instead of using first digit from build version.
UPDATE_NAME requires txGroupId to match original txGroupId used in REGISTER_NAME
UPDATE_GROUP requires txGroupId to match original txGroupId used in CREATE_GROUP
Extraneous JAXB unmarshal code removed from various transaction constructors.
Incorrect, old, groupID vs txGroupId checks removed from various transactions.
Fix bug in UPDATE_GROUP fromBase() method using mismatched column indexes.
Fix bug in API's pending transaction fetch not checking admin is of the same
group as the txGroupId. (Fix actually in HSQLDBTransactionRepository).
Similar fix in GroupApprovalTransaction.
Added POST /names/update for building an UPDATE-NAME transaction.
BlockGenerator now tries to validate new block after adding each
unconfirmed transaction in turn. If block becomes invalid then
that transaction is removed/skipped. This should further prevent
block jams. Skipped transactions might be deleted as the next block
is forged when unconfirmed transactions are collated/filtered/expired.
Add Block.deleteTransaction() for use during block generation above.
Block.addTransaction() and Block.deleteTransaction() use transaction
signatures to test for presence in Block's existing transactions.
Names shouldn't have stored registrant's public key!
"registrantPublicKey" removed from NameData Java object/bean.
Corresponding column removed from HSQLDB using ALTER TABLE but
also from the original CREATE TABLE definition. Remove the ALTER
TABLE statement just prior to rebuilding database!
(This needs to be applied to Polls too as some point).
Also, UpdateNameTransactions and BuyNameTransactions tables now
allow name_reference to be NULL as this column value isn't set
until the corresponding transactions are processed/added to a
block. (name_reference is a link to previous name-related
transaction that altered Name data like "owner" or "data" so
that name-related transactions can be orphaned/undone).
