Merge pull request bitcoin#42 from jonasnick/clarify-diagram

Clarify description of diagram

bip-taproot.mediawiki

@@ -208,7 +208,7 @@ def taproot_output_script(internal_pubkey, script_tree):
 
 The function <code>taproot_output_script</code> returns a byte array with the scriptPubKey. It can be P2SH wrapped if desired (see BIP141).
 
-[[File:bip-taproot/tree.png|frame|This diagram shows the hashing structure to obtain the tweak from an internal key ''P'' and a Merkle tree consisting of 3 script leaves.]]
+[[File:bip-taproot/tree.png|frame|This diagram shows the hashing structure to obtain the tweak from an internal key ''P'' and a Merkle tree consisting of 5 script leaves. ''A'', ''B'', ''C'' and ''E'' are ''TapLeaf'' hashes similar to ''D'' and ''AB'' is a ''TapBranch'' hash. Note that when ''CDE'' is computed ''E'' is hashed first because ''E'' is less than ''CD''.]]
 
 '''Spending using the internal key''' A Taproot output can be spent with the private key corresponding to the <code>internal_pubkey</code>. To do so, a witness stack consisting of a single element, a bip-schnorr signature on the signature hash as defined above, with the private key tweaked by the same <code>t</code> in the above snippet. See the code below: