Todd Gamblin authored Aug 27, 2011 and Brad King committed Sep 01, 2011

FindBoost now attempts to find Boost using find_package(Boost NO_MODULE)
before it does a module mode search.

User can now set any of these to Boost's install prefix to detect it in module
or config mode:

- Boost_DIR  for consistency with other CMake modules
- BOOST_ROOT or BOOSTROOT for adherence to boost convention