stewartmckee/cobweb — pull request #14 by mqzhang (2012-09-16 07:16:48+00:00)
Title: I think the gem need to require json when using it standalone

Hi,

when I was testing the gem today, and running the commands here :
```ruby
statistics = CobwebCrawler.new(:cache => 600).crawl("http://www.pepsico.com") do |page|
puts "Just crawled #{page[:url]} and got a status of #{page[:status_code]}."
end
```
got these errors:
```shell
!!!!!!!!!!!! ERROR !!!!!!!!!!!!!!!!
#1}:Hash>
[
[0] "/var/lib/gems/1.9.1/gems/cobweb-0.0.68/lib/stats.rb:88:in `update_statistics'",
[1] "/var/lib/gems/1.9.1/gems/cobweb-0.0.68/lib/cobweb_crawler.rb:85:in `block in crawl'"
]
```

So I think the gem need to require 'json' and modified the gemspec.

Thanks,
MQ