Add PromiseKit dependency

- Added PromiseKit dependency

Carthage/Checkouts/PromiseKit/Extensions/Bolts/Tests/TestBolts.swift

@@ -0,0 +1,23 @@
+import PromiseKit
+import PMKBolts
+import XCTest
+import Bolts
+
+class TestBolts: XCTestCase {
+    func test() {
+        let ex = expectation(description: "")
+
+        let value = { NSString(string: "1") }
+
+        firstly { () -> Promise<Void> in
+            return Promise()
+        }.then { _ -> BFTask<NSString> in
+            return BFTask(result: value())
+        }.done { obj in
+            XCTAssertEqual(obj, value())
+            ex.fulfill()
+        }
+
+        waitForExpectations(timeout: 1)
+    }
+}