* Explain that Arch/Manjaro/etc. need `-Dstatic=OFF` during the configure step
* move configuration options closer to that step
* separate sub-headers for configuration and build
Switch to target-oriented dependencies. Use imported targets for
dependencies (openssl, boost). Localize FindBoost to remove cmake
version dependence for latest boost support. Logically separate
"ripple-libpp" core sources and add install targets.
Add ninja build for msvc. Add two clang sanitizer builds. Misc script
changes to work with latest modernized cmake.