Introduced the notion of virtual hosts

This provides virtualized server configurations which take
effect after client connection when client hello is received.

Signed-off-by: Nikos Mavrogiannopoulos <nmav@gnutls.org>

tests/certs/server-cert-secp521r1.pem

@@ -0,0 +1,17 @@
+-----BEGIN CERTIFICATE-----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=
+-----END CERTIFICATE-----

tests/certs/server-key-secp521r1.pem

@@ -0,0 +1,50 @@
+Public Key Info:
+	Public Key Algorithm: EC/ECDSA
+	Key Security Level: Future (528 bits)
+
+curve:	SECP521R1
+private key:
+	01:f4:21:2c:21:9c:9c:55:b1:b6:82:45:62:ff:46:6c
+	2e:f9:bf:e9:25:65:49:83:50:18:fe:f1:93:5b:c7:83
+	26:dd:d0:03:0c:86:12:98:bb:0a:b8:18:34:d8:6c:30
+	ab:4f:23:d8:a8:57:02:d4:b2:4d:e6:e0:2b:79:33:e2
+	31:18:
+
+x:
+	46:20:9a:d4:0a:84:f6:86:e2:27:1a:9a:bb:c4:a5:2d
+	8f:6d:7c:5e:b1:4e:cc:31:e5:95:5e:0d:40:82:b6:b4
+	fa:3d:ad:9e:ba:5b:d2:f8:67:dd:82:fe:15:7a:c0:56
+	98:fb:39:9f:bb:24:db:48:24:c8:14:fa:04:1f:5a:8e
+	aa:
+
+y:
+	01:7b:63:02:89:02:ca:b6:3e:de:7e:fd:e9:dd:f5:bc
+	7f:de:d9:fc:50:4a:00:19:a3:f9:25:18:8c:8e:05:50
+	d8:1b:f4:d3:d7:e5:60:28:cb:66:af:ea:01:53:ba:fe
+	e9:fd:3e:69:98:60:28:50:96:91:c4:ea:22:dc:3f:66
+	53:4e:
+
+
+Public Key ID:
+	sha256:50:5D:17:4C:91:AF:86:F2:D2:B5:19:FB:1A:75:83:34:DF:EF:AA:35:D0:72:1A:FF:DC:7E:CC:B9:92:7B:75:CA
+	sha1:8E:25:3E:F2:A8:7D:D9:18:8F:E4:44:70:2F:2F:E3:49:D3:0A:F8:16
+Public key's random art:
++--[SECP521R1]----+
+|                 |
+|    . .          |
+|     o .         |
+|      o .        |
+|   . ..+S        |
+|  . E.O=o        |
+|   ..O+&.        |
+|   .o+X.o        |
+|  .oo..          |
++-----------------+
+
+-----BEGIN EC PRIVATE KEY-----
+MIHcAgEBBEIB9CEsIZycVbG2gkVi/0ZsLvm/6SVlSYNQGP7xk1vHgybd0AMMhhKY
+uwq4GDTYbDCrTyPYqFcC1LJN5uAreTPiMRigBwYFK4EEACOhgYkDgYYABABGIJrU
+CoT2huInGpq7xKUtj218XrFOzDHllV4NQIK2tPo9rZ66W9L4Z92C/hV6wFaY+zmf
+uyTbSCTIFPoEH1qOqgF7YwKJAsq2Pt5+/end9bx/3tn8UEoAGaP5JRiMjgVQ2Bv0
+09flYCjLZq/qAVO6/un9PmmYYChQlpHE6iLcP2ZTTg==
+-----END EC PRIVATE KEY-----