Fix BOOST_LIBRARIES not set problem and poolminer link error(miss OpenSSL) 

For unknown reason(upgrade to cmake 2.8.12?),  ${Boost_LIBRARIES} are now case sensitive and so BOOST_LIBRARIES was not set during find_package.

OpenSSL libraries are missed due to parent CMakeList.txt change?

Here is the pull request to fix, can reproduce by delete cache of Cmake on Window before merge.

should be common issue, but found ant test on window.