break up BIP39 tests so the individual ones run faster

...so that travis stops complaining about this otherwise slow test

test/test.BIP39.js

@@ -144,20 +144,24 @@ describe('BIP39', function() {
     it('should generate a mnemonic phrase', function() {
       var phrase = BIP39.mnemonic(BIP39WordlistEn, 128);
     });
-    it('should pass test vectors', function() {
-      var vectors = bip39_vectors['english'];
-      for (var v = 0 ; v < vectors.length ; v++) {
-        var vector = vectors[v];
-        var code = vector[0];
-        var mnemonic = vector[1];
-        var seed = vector[2];
-        var mnemonic1 = BIP39.entropy2mnemonic(BIP39WordlistEn, new Buffer(code, 'hex'));
-        var seed1 = BIP39.mnemonic2seed(mnemonic, 'TREZOR');
-        BIP39.check(BIP39WordlistEn, mnemonic).should.be.true;
-        mnemonic1.should.equal(mnemonic);
-        seed1.toString('hex').should.equal(seed)
-      }
-    });
+
+    var vectors = bip39_vectors['english'];
+    for (var v = 0 ; v < vectors.length ; v++) {
+      (function(v){
+        it('should pass test vector ' + v, function() {
+          var vector = vectors[v];
+          var code = vector[0];
+          var mnemonic = vector[1];
+          var seed = vector[2];
+          var mnemonic1 = BIP39.entropy2mnemonic(BIP39WordlistEn, new Buffer(code, 'hex'));
+          var seed1 = BIP39.mnemonic2seed(mnemonic, 'TREZOR');
+          BIP39.check(BIP39WordlistEn, mnemonic).should.be.true;
+          mnemonic1.should.equal(mnemonic);
+          seed1.toString('hex').should.equal(seed)
+        });
+      })(v);
+    }
+
   });
 
 });