Tidy up examples folder

examples/blind.vp

-// SPDX-FileCopyrightText: © 2019-2021 Nadim Kobeissi <nadim@symbolic.software>
-// SPDX-License-Identifier: GPL-3.0-only
-
-attacker[active]
-
-principal Alice[
-	generates k
-	knows private m
-	b = BLIND(k, m)
-]
-
-Alice -> Sarah: b
-
-principal Sarah[
-	knows private s
-	gs = G^s
-	blindsig = SIGN(s, b)
-]
-
-Sarah -> Alice: blindsig, gs
-
-principal Alice[
-	unblindedsig = UNBLIND(k, m, blindsig)
-	_ = SIGNVERIF(gs, m, unblindedsig)?
-]
-
-queries[
-	confidentiality? m
-]

examples/proverif/ffgg.pv

-type skey.
-type pkey.
-type nonce.
-
-fun pk(skey): pkey.
-fun encrypt(bitstring, pkey): bitstring.
-reduc forall x: bitstring, y: skey; decrypt(encrypt(x,pk(y)),y) = x.
-
-free c: channel.
-free M: nonce [private].
-
-query attacker(M).
-
-let processA(pkB: pkey) = 
-	in(c,(n1: nonce, n2: nonce));
-	out(c, encrypt((n1, n2, M ), pkB)).
-
-let processB(skB: skey, pkB: pkey) = 
-        new n1: nonce; new n2: nonce;
-	out(c, (n1, n2));
-	in(c, mes: bitstring);
-	let (=n1, x1: nonce, x2: nonce) = decrypt(mes, skB) in
-	out(c, (x1, encrypt((x1, x2, n1), pkB))).
-
-process 
-    new skB: skey; let pkB = pk(skB) in
-    out(c, pkB);
-    ((!processA(pkB)) | (!processB(skB, pkB)))

examples/tls13.vp

-// SPDX-FileCopyrightText: © 2019-2021 Nadim Kobeissi <nadim@symbolic.software>
-// SPDX-License-Identifier: GPL-3.0-only
-
-attacker[active]
-
-principal Client[
-	generates clientRandom
-	generates c
-	gc = G^c
-]
-
-principal Server[
-	knows private certificateKey
-	knows public hostname
-	generates serverRandom
-	generates s
-	gs = G^s
-	certificate = HASH(certificateKey, hostname)
-	gCertificate = G^certificateKey
-]
-
-Client -> Server: clientRandom, [gc]
-
-Server -> Client: serverRandom, [gs]
-
-principal Server[
-	knows public derived
-	knows public c_hs_traffic
-	knows public s_hs_traffic
-	knows public key
-	knows public iv
-	sharedSecretServer = gc^s
-	helloHashServer = HASH(clientRandom, gc, serverRandom, gs)
-	earlySecretServer = HKDF(nil, nil, nil)
-	emptyHashServer = HASH(nil)
-	derivedSecretServer = HKDF(earlySecretServer, derived, emptyHashServer)
-	handshakeSecretServer = HKDF(derivedSecretServer, sharedSecretServer, nil)
-	clientHandshakeTrafficSecretServer = HKDF(handshakeSecretServer, c_hs_traffic, helloHashServer)
-	serverHandshakeTrafficSecretServer = HKDF(handshakeSecretServer, s_hs_traffic, helloHashServer)
-	clientHandshakeKeyServer = HKDF(clientHandshakeTrafficSecretServer, key, nil)
-	serverHandshakeKeyServer = HKDF(serverHandshakeTrafficSecretServer, key, nil)
-	clientHandshakeIVServer = HKDF(clientHandshakeTrafficSecretServer, iv, nil)
-	serverHandshakeIVServer = HKDF(serverHandshakeTrafficSecretServer, iv, nil)
-]
-
-principal Client[
-	knows public derived
-	knows public c_hs_traffic
-	knows public s_hs_traffic
-	knows public key
-	knows public iv
-	sharedSecretClient = gs^c
-	helloHashClient = HASH(clientRandom, gc, serverRandom, gs)
-	earlySecretClient = HKDF(nil, nil, nil)
-	emptyHashClient = HASH(nil)
-	derivedSecretClient = HKDF(earlySecretClient, derived, emptyHashClient)
-	handshakeSecretClient = HKDF(derivedSecretClient, sharedSecretClient, nil)
-	clientHandshakeTrafficSecretClient = HKDF(handshakeSecretClient, c_hs_traffic, helloHashClient)
-	serverHandshakeTrafficSecretClient = HKDF(handshakeSecretClient, s_hs_traffic, helloHashClient)
-	clientHandshakeKeyClient = HKDF(clientHandshakeTrafficSecretClient, key, nil)
-	serverHandshakeKeyClient = HKDF(serverHandshakeTrafficSecretClient, key, nil)
-	clientHandshakeIVClient = HKDF(clientHandshakeTrafficSecretClient, iv, nil)
-	serverHandshakeIVClient = HKDF(serverHandshakeTrafficSecretClient, iv, nil)
-]
-
-principal Server[
-	e1 = AEAD_ENC(serverHandshakeKeyServer, certificate, nil)
-	certVerifyServer = SIGN(certificateKey, HASH(helloHashServer, e1))
-	e2 = AEAD_ENC(serverHandshakeKeyServer, certVerifyServer, nil)
-	e3 = AEAD_ENC(serverHandshakeKeyServer, gCertificate, nil)
-]
-
-Server -> Client: e1, e2, e3
-
-principal Client[
-	d1 = AEAD_DEC(serverHandshakeKeyClient, e1, nil)?
-	d2 = AEAD_DEC(serverHandshakeKeyClient, e2, nil)?
-	d3 = AEAD_DEC(serverHandshakeKeyClient, e3, nil)?
-	_ = SIGNVERIF(d3, HASH(helloHashClient, e1), d2)?
-]
-
-principal Server[
-]
-
-queries[
-	confidentiality? certificate
-]