FIPS issues with handling "traditional" PEM key files

This patch set modifies the PEM handling routines to work with the new PKCS#8 PEM files that are used by OpenSSL by default since OpenSSL 1.0.0 and abandons the old "traditional" PEM format (dependent on insecure MD5), even though by default, it can still read it.

This actually adds also the FIPS target to CI (emulated), which is currently very broken because there are many encrypted private keys in the old format that can not be read in FIPS mode (MD5 is disabled).