Fix missing include in core/dense.hpp
Fix missing include in core/dense.hpp

Ignore-this: 5d3715a249db267d4ddf85134a5a71d3

darcs-hash:20150313182914-fa073-e7228def418853828b7fbf1de50181f647d778c5

rogiervd/flipsta,rogiervd/flipsta,rogiervd/flipsta