Fixed locating cryptopp in system locations
Look at the contents of CMake variables
Do not assume that the build dir is called cpp-ethereum-build.
Fixed typo.
Merge pull request #23 from SharpCoiner/buildpatch

Do not assume that the build dir is called cpp-ethereum-build.
Merge pull request #20 from danielhams/master

Reject local addresses during interface discovery
Merge pull request #22 from austonst/master

Fixed locating cryptopp in system locations