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 makes the regex in `HttpClient.cpp` that matches the content-length http header case insensitive to improve compatibility, as http headers are case insensitive.
This updates Boost to 1.88, which is needed because Clio wants to move to 1.88 as that fixes several ASAN false positives around coroutine usage. In order for Clio to move to newer boost, libXRPL needs to move too. Hence the changes in this PR. A lot has changed between 1.83 and 1.88 so there are lots of changes in the diff, especially in regards to Boost.Asio and coroutines in particular.
