Allow default:false value for confirm.

lib/prompts/confirm.js

@@ -23,9 +23,17 @@ module.exports = Prompt;
 function Prompt() {
   Base.apply(this, arguments);
 
+  var defaultValue = this.opt.default;
+
+  if (_.isString(defaultValue)) {
+    defaultValue = defaultValue !== "false";
+  } else if (_.isUndefined(this.opt.default)) {
+    defaultValue = true;
+  }
+
   _.extend(this.opt, {
     filter: function(input) {
-      var value = true;
+      var value = defaultValue;
       if (input != null && input !== "") {
         value = /^y(es)?/i.test(input);
       }

test/specs/prompts/confirm.js

@@ -64,4 +64,66 @@ describe("`confirm` prompt", function() {
     this.rl.emit("line", "bla bla foo");
   });
 
+    describe("should accept a default value", function() {
+
+    it("should allow a default value", function(done) {
+
+      var falseConfirm = new Confirm({
+        message: "foo bar",
+        default: false
+      }, this.rl);
+
+      falseConfirm.run(function(answer) {
+        expect(answer).to.be.false;
+        done();
+      });
+
+      this.rl.emit("line", "");
+    });
+
+    it("should default \"true\" to boolean true", function(done) {
+
+      var falseConfirm = new Confirm({
+        message: "foo bar",
+        default: "true"
+      }, this.rl);
+
+      falseConfirm.run(function(answer) {
+        expect(answer).to.be.true;
+        done();
+      });
+
+      this.rl.emit("line", "");
+    });
+
+    it("should default \"false\" to boolean false", function(done) {
+      var falseConfirm = new Confirm({
+        message: "foo bar",
+        default: "false"
+      }, this.rl);
+
+      falseConfirm.run(function(answer) {
+        expect(answer).to.be.false;
+        done();
+      });
+
+      this.rl.emit("line", "");
+    });
+
+    it("should default any other string than \"true\" to boolean true", function(done) {
+      var falseConfirm = new Confirm({
+        message: "foo bar",
+        default: "asdfdsa"
+      }, this.rl);
+
+      falseConfirm.run(function(answer) {
+        expect(answer).to.be.true;
+        done();
+      });
+
+      this.rl.emit("line", "");
+    });
+
+  });
+
 });