Update boost to 1.56.
Add support for VS 2012.
Update VS 2010 solution for use with updated boost library. Also add boost_chrono to build.
Merge pull request #33 from chris20/develop

Update boost to 1.56 (#8bbea3a)
Add support for VS 2012 (#c1e0ae9)
Update VS 2010 solution for use with updated boost library. Also add boost_chrono to build. (#45f6e0b)