This change renames all occurrences of `namespace ripple` and `ripple::` to `namespace xrpl` and `xrpl::`, respectively, as well as the names of test suites. It also provides a script to allow developers to replicate the changes in their local branch or fork to avoid conflicts.
This change renames all the `info()` functions to `header()`, since they return `LedgerHeader` structs. It also renames the underlying variables from `info_` to `header_`.
This PR cleans up `RPCHelpers.h` and `RPCHelpers.cpp`. It splits out all the fetch-ledger functions to a new set of files, `RPCLedgerHelpers.h`/`RPCLedgerHelpers.cpp`, and moves the general-API functions to `ApiVersion.h`. There is no functionality change.
