update api support script

[Hexmagic]

have a look at this issue #46

[Hexmagic]

I only change this method by add a param script ,so I can use script to update document

def update(self, index, type, uid, contents,script=False,callback=None):
        path = "/%(index)s/%(type)s/%(uid)s/_update" % {
            "index": index,
            "type": type,
            "uid": uid
        }
        if script:
            partial = contents
        else:    
            partial = { "doc": contents }

why all checks failed, and got error

Traceback (most recent call last):
  File "/home/travis/build/globocom/tornado-es/tornadoes/tests/unit/test_tornadoes.py", line 22, in tearDown
    if (not IOLoop.initialized() or self.io_loop is not IOLoop.instance()):
AttributeError: type object 'IOLoop' has no attribute 'initialized'