[release/1.3.4] cmd/utils, params: homestead block

(cherry picked from commit e22fd22c97b4f5d4af118dca3fb2cb6292a520a6)

Conflicts:
	cmd/utils/flags.go

params/util.go

@@ -18,7 +18,11 @@ package params
 
 import "math/big"
 
-var HomesteadBlock *big.Int = big.NewInt(2000000)
+var (
+	TestNetHomesteadBlock = big.NewInt(494000)    // testnet homestead block
+	MainNetHomesteadBlock = big.NewInt(1150000)   // mainnet homestead block
+	HomesteadBlock        = MainNetHomesteadBlock // homestead block used to check against
+)
 
 func IsHomestead(blockNumber *big.Int) bool {
 	// for unit tests TODO: flip to true after homestead is live