“The libssh2 library is required by this module.  If you don't have it, you can download it from http://www.libssh2.org; you may also need OpenSSL, which can be obtained from http://www.openssl.org.

Debian:   sudo aptitude install libssh2-1-dev
OpenSUSE: sudo zypper in libssh2-1 libssh2-devel

Can't link/include ‘libssh2.h’, 'ssh2'