Merge pull request bitcoin#565 from sipa/bip-witaddr

Update BIP173: new reference impls + tests fix

Author: luke-jr

bip-0173.mediawiki

@@ -227,6 +227,12 @@ program is neither 20 nor 32 bytes, the script must fail.''
 As a result of the previous rules, addresses are always between 14 and 74 characters long, and their length modulo 8 cannot be 0, 3, or 5.
 Version 0 witness addresses are always 42 or 62 characters, but implementations MUST allow the use of any version.
 
+Implementations should take special care when converting the address to a
+scriptPubkey, where witness version ''n'' is stored as ''OP_n''. OP_0 is
+encoded as 0x00, but OP_1 through OP_16 are encoded as 0x51 though 0x60
+(81 to 96 in decimal). If a bech32 address is converted to an incorrect
+scriptPubKey the result will likely be either unspendable or insecure.
+
 ===Compatibility===
 
 Only new software will be able to use these addresses, and only for
@@ -242,8 +248,10 @@ P2PKH addresses can be used.
 * Reference encoder and decoder:
 ** [https://github.com/sipa/bech32/tree/master/ref/c For C]
 ** [https://github.com/sipa/bech32/tree/master/ref/javascript For JavaScript]
+** [https://github.com/sipa/bech32/tree/master/ref/go For Go]
 ** [https://github.com/sipa/bech32/tree/master/ref/python For Python]
 ** [https://github.com/sipa/bech32/tree/master/ref/haskell For Haskell]
+** [https://github.com/sipa/bech32/tree/master/ref/ruby For Ruby]
 ** [https://github.com/sipa/bech32/tree/master/ref/rust For Rust]
 
 * Fancy decoder that localizes errors:
@@ -264,9 +272,9 @@ The following list gives valid segwit addresses and the scriptPubKey that they
 translate to in hex.
 * <tt>BC1QW508D6QEJXTDG4Y5R3ZARVARY0C5XW7KV8F3T4</tt>: <tt>0014751e76e8199196d454941c45d1b3a323f1433bd6</tt>
 * <tt>tb1qrp33g0q5c5txsp9arysrx4k6zdkfs4nce4xj0gdcccefvpysxf3q0sl5k7</tt>: <tt>00201863143c14c5166804bd19203356da136c985678cd4d27a1b8c6329604903262</tt>
-* <tt>bc1pw508d6qejxtdg4y5r3zarvary0c5xw7kw508d6qejxtdg4y5r3zarvary0c5xw7k7grplx</tt>: <tt>8128751e76e8199196d454941c45d1b3a323f1433bd6751e76e8199196d454941c45d1b3a323f1433bd6</tt>
-* <tt>BC1SW50QA3JX3S</tt>: <tt>9002751e</tt>
-* <tt>bc1zw508d6qejxtdg4y5r3zarvaryvg6kdaj</tt>: <tt>8210751e76e8199196d454941c45d1b3a323</tt>
+* <tt>bc1pw508d6qejxtdg4y5r3zarvary0c5xw7kw508d6qejxtdg4y5r3zarvary0c5xw7k7grplx</tt>: <tt>5128751e76e8199196d454941c45d1b3a323f1433bd6751e76e8199196d454941c45d1b3a323f1433bd6</tt>
+* <tt>BC1SW50QA3JX3S</tt>: <tt>6002751e</tt>
+* <tt>bc1zw508d6qejxtdg4y5r3zarvaryvg6kdaj</tt>: <tt>5210751e76e8199196d454941c45d1b3a323</tt>
 * <tt>tb1qqqqqp399et2xygdj5xreqhjjvcmzhxw4aywxecjdzew6hylgvsesrxh6hy</tt>: <tt>0020000000c4a5cad46221b2a187905e5266362b99d5e91c6ce24d165dab93e86433</tt>
 
 The following list gives invalid segwit addresses and the reason for