Modify split to handle values containing '='

If param contains more than one '=' the split will return error. E.g:
url240=http://cs540403v4.vk.me/u01234/videos/blabla.mp4?extra=ZIH4SI05-2Gsds

File "/xyz/plugin.video.dreamfilm/resolvers.py", line 18, in vk_streams
                                            key, value = param.split('=')
                                            ValueError: too many values to unpack