Merge pull request bitcoin#472 from afk11/bip39-allowed-sizes

BIP39: 'recommended size' -> 'allowed size'

Author: luke-jr

bip-0039.mediawiki

@@ -33,7 +33,7 @@ sentences (also known as brainwallets) into a wallet seed.
 
 The mnemonic must encode entropy in a multiple of 32 bits. With more entropy
 security is improved but the sentence length increases. We refer to the
-initial entropy length as ENT. The recommended size of ENT is 128-256 bits.
+initial entropy length as ENT. The allowed size of ENT is 128-256 bits.
 
 First, an initial entropy of ENT bits is generated. A checksum is generated by
 taking the first <pre>ENT / 32</pre> bits of its SHA256 hash. This checksum is