CH08: clarify that diff sigs in the same input can have diff sighashes

chapters/signatures.adoc

@@ -132,10 +132,10 @@ three signed inputs may have three signatures with different +SIGHASH+
 flags, each signature signing (committing) different parts of the
 transaction.
 
-Remember, each input may contain a signature in its unlocking script. As
-a result, a transaction that contains several inputs may have signatures
+Remember, each input may contain one or more signatures. As
+a result, an input may have signatures
 with different +SIGHASH+ flags that commit different parts of the
-transaction in each of the inputs. Note also that bitcoin transactions
+transaction. Note also that bitcoin transactions
 may contain inputs from different "owners," who may sign only one input
 in a partially constructed transaction, collaborating with
 others to gather all the necessary signatures to make a valid