mongo queue: drop clear_on_init & clear_on_exit options, change method of generation of collection name if it was not defined explicitly
Add get_name method to Spider class. Add grab.util.misc.camel_case_to_underscore function to build spider name from the name of its class.
Add additional argument to constructor of queue class: spider_name
Add new standart script `crawl` which is used to run spiders. Add ability to specify spider settings via settings file