ASAN wasn't able to keep track of `boost::coroutine` context switches, and would lead to many false positives being detected. By switching to `boost::coroutine2` and `ucontext`, ASAN is able to know about the context switches advertised by the `boost::fiber` class, which in turn leads to more cleaner ASAN analysis.
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.
