Replace uses of deprecated new Buffer with Buffer.from

Author: whymarrh

index.js

@@ -16,11 +16,11 @@ const rlp = ethUtil.rlp
 // geth compatible db keys
 const headHeaderKey = 'LastHeader' // current canonical head for light sync
 const headBlockKey = 'LastBlock' // current canonical head for full sync
-const headerPrefix = new Buffer('h') // headerPrefix + number + hash -> header
-const tdSuffix = new Buffer('t') // headerPrefix + number + hash + tdSuffix -> td
-const numSuffix = new Buffer('n') // headerPrefix + number + numSuffix -> hash
-const blockHashPrefix = new Buffer('H') // blockHashPrefix + hash -> number
-const bodyPrefix = new Buffer('b') // bodyPrefix + number + hash -> block body
+const headerPrefix = Buffer.from('h') // headerPrefix + number + hash -> header
+const tdSuffix = Buffer.from('t') // headerPrefix + number + hash + tdSuffix -> td
+const numSuffix = Buffer.from('n') // headerPrefix + number + numSuffix -> hash
+const blockHashPrefix = Buffer.from('H') // blockHashPrefix + hash -> number
+const bodyPrefix = Buffer.from('b') // bodyPrefix + number + hash -> block body
 
 // utility functions
 const bufBE8 = n => n.toArrayLike(Buffer, 'be', 8) // convert BN to big endian Buffer