upgrade scrapylib item processors

so we get rid of this warning when running tests:

> /local/lib/python2.7/site-packages/scrapylib/processors/**init**.py:8: ScrapyDeprecationWarning: Module `scrapy.contrib.loader.processor` is deprecated, use `scrapy.loader.processors` instead
>   from scrapy.contrib.loader.processor import Compose, MapCompose, TakeFirst
