wrong check for boost libraries in configure.ac

The configure.ac file checks for the presence of various Boost libraries by checking the presence of certain header files. Unfortunately, Boost packaging has changed so that headers come from a different package than development library binaries do, so you get a failure in 'make check' when the boost packages are noit installed, even though the configure thinks they are installed.

For example, Nux's configure.ac checks for the presence of boost/filesystem/fstream.hpp to see if boost_filesystem.so is present, but the header comes from libboost1.XX-dev and the library from the libboost-filesystem1.XX-dev package.