Now any long time consuming function can be invoked in separate thread in chain context

 In following example we define class `Example` with `execute` method which returns `ChainFactory` object with two functions in it. After `execute` is invoked, there will be 100 sleeps done in separate thread, so noone would be blocked:
 ```
 class Example(object):
    def execute(self):
        return ChainFactory([self.do100SleepsOneByOne, lambda r: sys.stdout.write('Done!')])

    def do100SleepsOneByOne(self):
        for _ in xrange(100):
            result = yield self.sleep(0.01)

    @chain.threaded
    def sleep(self, t):
        time.sleep(t)
        return 'Arrrgh! You woke me up', t
 ```
Exception rethrow

 - now exceptions thrown in other thread would be rethrown in chain thread
Cocaine tools now have experimental `AppUploadFromRepositoryAction` action to upload application from git repository. Also some fixes done

 - `threading` thread is now daemon - temporary solution to be able to terminate it if some error occurred (e.g. TimeoutError)