smartcontract: change value of NEP11Payable and NEP17Payable

The essence is the same, but the standard has its official name since
neo-project/proposals#169.

Signed-off-by: Anna Shaleva <[email protected]>

Author: AnnaShaleva

pkg/smartcontract/manifest/manifest.go

@@ -22,10 +22,12 @@ const (
 	NEP11StandardName = "NEP-11"
 	// NEP17StandardName represents the name of NEP-17 smartcontract standard.
 	NEP17StandardName = "NEP-17"
-	// NEP11Payable represents the name of contract interface which can receive NEP-11 tokens.
-	NEP11Payable = "NEP-11-Payable"
-	// NEP17Payable represents the name of contract interface which can receive NEP-17 tokens.
-	NEP17Payable = "NEP-17-Payable"
+	// NEP11Payable represents the name of NEP-26 smartcontract standard (contract interface
+	// which can receive NEP-11 tokens)
+	NEP11Payable = "NEP-26"
+	// NEP17Payable represents the name of NEP-27 smartcontract standard (contract interface
+	// which can receive NEP-17 tokens).
+	NEP17Payable = "NEP-27"
 	// NEP24StandardName represents the name of the NEP-24 smart contract standard for NFT royalties.
 	NEP24StandardName = "NEP-24"
 	// NEP24Payable represents the name of the contract interface for handling royalty payments in accordance