This change introduces a new fix amendment (`fixPayChanV1`) that prevents the creation of new `PaymentChannelCreate` transaction with a `CancelAfter` time less than the current ledger time. It piggy backs off of fix1571.
Once the amendment is activated, creating a new `PaymentChannel` will require that if you specify the `CancelAfter` time/value, that value must be greater than or equal to the current ledger time.
Currently users can create a payment channel where the `CancelAfter` time is before the current ledger time. This results in the payment channel being immediately closed on the next PaymentChannel transaction.
Requiring manual updates of numFeatures is an annoying manual process that is easily forgotten, and leads to frequent merge conflicts. This change takes advantage of the `XRPL_FEATURE` and `XRPL_FIX` macros, and adds a new `XRPL_RETIRE` macro to automatically set `numFeatures`.
- spec: XRPLF/XRPL-Standards#220
- amendment: "DeepFreeze"
- implemented deep freeze spec to allow token issuers to prevent currency holders from being able to acquire more of these tokens.
- in combination with normal freeze, deep freeze effectively prevents any balance trust line balance change of a currency holder (except direct issuer <-> holder payments).
- added 2 new invariant checks to verify that deep freeze cannot be enacted without normal freeze and transfer is not frozen.
- made some fixes to existing freeze handling.
Co-authored-by: Ed Hennis <ed@ripple.com>
Co-authored-by: Howard Hinnant <howard.hinnant@gmail.com>
