bip-46: fix typo

Author: storopoli

bip-0046.mediawiki

@@ -107,7 +107,7 @@ A certificate message can be created by another application external to this sta
 
 Almost all wallets implementing this standard can use their already-existing "Sign Message" function to sign the certificate message. As the certificate message itself is always an ASCII string, the wallet may not need to specially implement this section at all but just rely on users copypasting their certificate message into the already-existing "Sign Message" user interface. This works as long as the wallet knows how to use the private key of the timelocked address for signing messages.
 
-It is most important for wallet implementions of this standard to support creating the certificate signature. Verifying the certificate signature is less important.
+It is most important for wallet implementations of this standard to support creating the certificate signature. Verifying the certificate signature is less important.
 
 
 == Test vectors ==