Merge pull request #3499 from ripcurlx/set-unsigned-to-na

[1.2.0] Unsigned should be N/A

core/src/main/resources/i18n/displayStrings.properties

@@ -346,7 +346,7 @@ offerbook.timeSinceSigning.daysSinceSigning.long={0} since signing
 offerbook.timeSinceSigning.help=When you successfully complete a trade with a peer who has a signed payment account, your payment account is signed.\n\
    {0} days later, the initial limit of {1} is lifted and your account can sign other peers'' payment accounts.
 offerbook.timeSinceSigning.notSigned=Not signed yet
-offerbook.timeSinceSigning.notSigned.noNeed=Unsigned
+offerbook.timeSinceSigning.notSigned.noNeed=N/A
 shared.notSigned=This account hasn't been signed yet
 shared.notSigned.noNeed=This account type doesn't use signing