Parsing of PKCS#8 encrypted private key files added and PKCS#12 basis

PKCS#8 encrypted key file support has been added to x509parse_key() with
support for some PCKS#12 PBE functions (pbeWithSHAAnd128BitRC4,
pbeWithSHAAnd3-KeyTripleDES-CBC and pbeWithSHAAnd2-KeyTripleDES-CBC)
(cherry picked from commit cf6e95d9a81c7b22271beb58a09b5c756148e62a)

Conflicts:
	scripts/generate_errors.pl
diff --git a/library/Makefile b/library/Makefile
index e878583..72f8566 100644
--- a/library/Makefile
+++ b/library/Makefile
@@ -47,7 +47,7 @@
 		md4.o		md5.o		net.o			\
 		oid.o									\
 		padlock.o	pbkdf2.o	pem.o			\
-		pkcs11.o								\
+		pkcs11.o	pkcs12.o					\
 		rsa.o		sha1.o		sha2.o			\
 		sha4.o		ssl_cache.o	ssl_cli.o		\
 		ssl_srv.o   ssl_ciphersuites.o			\