Per XLS-0095, we are taking steps to rename ripple(d) to xrpl(d).
This change specifically removes all copyright notices referencing Ripple, XRPLF, and certain affiliated contributors upon mutual agreement, so the notice in the LICENSE.md file applies throughout. Copyright notices referencing external contributions remain as-is. Duplicate verbiage is also removed.
This change excludes from Codecov unreachable/difficult-to-test transaction code (such as `tecINTERNAL`) and old code (from amendments that have been enabled for a long time that are only around for ledger replay reasons). This removes about 200 lines of misses and increases the Codecov coverage by 0.3% (79.2% to 79.5%).
