Sub in std::array for boost::array and beast::FixedArray
Force BOOST_ASIO_HAS_STD_ARRAY to 1
for the clang / gcc libstdc++ 4.8 combination
Add standalone testsuite builds to SConstruct
[WIP] Autobridge test implementation
New classes for processing offers in order books:
* BookTip provides consume-and-step offer traversal
* OfferStream applies offer business rules and presents offers to callers
* Quality class opaque type encapsulates quality logic
* Taker class manages state for the active party during order processing
* Offer class wraps book offers for presentation
* Amounts class holds in and out quantities
[FOLD] small const-ness