Edited ch08_signatures.adoc with Atlas code editor

ch08_signatures.adoc

@@ -1,7 +1,7 @@
 [[c_signatures]]
 == Digital Signatures
 
-Two signature algorithms are currently
+Two ((("digital signatures", "schnorr signature algorithm")))((("schnorr signature algorithm")))((("digital signatures", "ECDSA")))((("ECDSA (Elliptic Curve Digital Signature Algorithm)")))signature algorithms are currently
 used in Bitcoin, the _schnorr signature algorithm_ and the _Elliptic
 Curve Digital Signature Algorithm_ (_ECDSA_).
 These algorithms are used for digital signatures based on elliptic
@@ -13,7 +13,7 @@ keypath spending, and by the script functions +OP_CHECKSIG+,
 Any time one of those is executed, a signature must be
 provided.
 
-A digital signature serves
+A digital signature((("digital signatures", "purpose of"))) serves
 three purposes in Bitcoin. First, the
 signature proves that the controller of a private key, who is by
 implication the owner of the funds, has _authorized_ the spending of