Tests: updated ssl_engine_keys.t test. After merge with libp11, pkcs11 engine shared object was renamed from "engine_pkcs11.so" to "pkcs11.so". Changed configuration accordingly. Additionally, changed "init" to "1" in the engine configuration. This keeps pkcs11 engine loaded and prevents segmentation faults observed during nginx shutdown. While here, restored correct order of ssl_certificate and ssl_certificate_key.