Lose the boost dependency since recent versions of capnproto's kj
also provide a nice filesystem library. Take the opportunity to
refactor the Run object to become more than POD and to encapsulate
some of the functionality that was done in the Laminar class
Part of #49 refactor
Now that capnp/kj provides http and websocket functions, replace
the excellent websocketpp library with the kj functions. This
removes a dependency and allows for more consistent idiomatic
code. Thanks websocketpp, it was great to have you along!
This should enable parts of the refactor described in #49