Rename getEmail -> setEmail

It doesn't really return the email address; it mutates the ACMEIssuer.

account.go

@@ -171,14 +171,14 @@ func (am *ACMEIssuer) saveAccount(ctx context.Context, ca string, account acme.A
 	return storeTx(ctx, am.config.Storage, all)
 }
 
-// getEmail does everything it can to obtain an email address
+// setEmail does everything it can to obtain an email address
 // from the user within the scope of memory and storage to use
 // for ACME TLS. If it cannot get an email address, it does nothing
 // (If user is prompted, it will warn the user of
 // the consequences of an empty email.) This function MAY prompt
 // the user for input. If allowPrompts is false, the user
 // will NOT be prompted and an empty email may be returned.
-func (am *ACMEIssuer) getEmail(ctx context.Context, allowPrompts bool) error {
+func (am *ACMEIssuer) setEmail(ctx context.Context, allowPrompts bool) error {
 	leEmail := am.Email
 
 	// First try package default email, or a discovered email address

account_test.go

@@ -171,7 +171,7 @@ func TestGetEmailFromPackageDefault(t *testing.T) {
 	}
 	am.config = testConfig
 
-	err := am.getEmail(ctx, true)
+	err := am.setEmail(ctx, true)
 	if err != nil {
 		t.Fatalf("getEmail error: %v", err)
 	}
@@ -203,7 +203,7 @@ func TestGetEmailFromUserInput(t *testing.T) {
 
 	email := "test3@foo.com"
 	stdin = bytes.NewBufferString(email + "\n")
-	err := am.getEmail(ctx, true)
+	err := am.setEmail(ctx, true)
 	if err != nil {
 		t.Fatalf("getEmail error: %v", err)
 	}
@@ -263,7 +263,7 @@ func TestGetEmailFromRecent(t *testing.T) {
 			t.Fatalf("Could not change user folder mod time for '%s': %v", eml, err)
 		}
 	}
-	err := am.getEmail(ctx, true)
+	err := am.setEmail(ctx, true)
 	if err != nil {
 		t.Fatalf("getEmail error: %v", err)
 	}

acmeissuer.go

@@ -226,7 +226,7 @@ func (am *ACMEIssuer) PreCheck(ctx context.Context, names []string, interactive
 			}
 		}
 	}
-	return am.getEmail(ctx, interactive)
+	return am.setEmail(ctx, interactive)
 }
 
 // Issue implements the Issuer interface. It obtains a certificate for the given csr using