Bleeding Hollow

Added

• Introduce new development handler with eye-candy colored output.

Changed

• Note, that there are some symbols, that are wrapped into experimental namespace. These symbols don't adhere semantic versioning and, well... experimental. Use them with caution and only, where you want to try super-unstable features, which can be changed or even dropped.
• Hide boost::asio::detail namespace, which are supposed to be hidden by default, but the ancient GNU linker exports them anyway.