Replace Journal public data members with member function accessors
in order to make Journal lighter weight. The change makes a
Journal cheaper to pass by value.
Also add missing stream checks (e.g., calls to JLOG) to avoid
text processing that ultimately will not be stored in the log.
Add a new algorithm for finding the liquidity in a payment path. There
is still a reverse and forward pass, but the forward pass starts at the
limiting step rather than the payment source. This insures the limiting
step is completely consumed rather than potentially leaving a 'dust'
amount in the forward pass.
Each step in a payment is either a book step, a direct step (account to
account step), or an xrp endpoint. Each step in the existing
implementation is a triple, where each element in the triple is either
an account of a book, for a total of eight step types.
Since accounts are considered in pairs, rather than triples, transfer
fees are handled differently. In V1 of payments, in the payment path
A -> gw ->B, if A redeems to gw, and gw issues to B, a transfer fee is
changed. In the new code, a transfer fee is changed even if A issues to
gw.
In some cases multiplying or dividing STAmounts gave incorrect results.
This happens when:
1) The result should be rounded up
2) The STAmount represents a native value (XRP)
3) The rounded up value was less than one drop
In this case, the result was zero, instead of one drop. This could
cause funded offers to be removed as unfunded.
Include the ledger sequence number in fee change transactions to ensure
each such transaction has a unique transaction ID.
We tolerate the absence of a ledger sequence in fee change transactions so
that past fee change transactions remain parseable. Since no live amendment
transactions have yet happened, there is no need to tolerate an absent
ledger sequence there.
The caller of the account_info RPC command can optionally
specify that they want the account's SignerList returned by
adding the argument:
"signer_lists": "true"
The returned SignerList is in an array. This leaves us room to
support multiple signer lists on an account in the future without
changing the syntax of the result.
The command-line version of account_info does not support the new
option.
With the addition of multisigning there are a variety of reasons
a signature may fail. We now return a more descriptive message
for the reason certain signature checks fail.
