Remove nokogiri and use regex to parse crtsh responses

aquatone.gemspec

@@ -21,7 +21,6 @@ Gem::Specification.new do |spec|
   spec.require_paths = ["lib"]
 
   spec.add_dependency "httparty", "~> 0.14.0"
-  spec.add_dependency "nokogiri", "~> 1.8.0"
   spec.add_dependency "childprocess", "~> 0.7.0"
 
   spec.add_development_dependency "bundler", "~> 1.13"

lib/aquatone.rb

@@ -7,7 +7,6 @@
 
 require "httparty"
 require "childprocess"
-require "nokogiri"
 
 require "aquatone/version"
 require "aquatone/port_lists"

lib/aquatone/collector.rb

@@ -66,10 +66,6 @@ def post_request(uri, body=nil, options={})
       Aquatone::HttpClient.post(uri, options)
     end
 
-    def parse_html(html)
-      Nokogiri::HTML(html)
-    end
-
     def url_escape(string)
       CGI.escape(string)
     end

lib/aquatone/collectors/crtsh.rb

@@ -10,10 +10,8 @@ class Crtsh < Aquatone::Collector
       def run
         response = get_request("https://crt.sh/?dNSName=%25.#{url_escape(domain.name)}")
 
-        parsed = parse_html(response.body)
-
-        parsed.css('table').css('table').css('tr').css('td:nth-child(4)').map do |column|
-          add_host(column.text.gsub("*.", ""))
+        response.body.to_enum(:scan, /<TD>([a-zA-Z0-9_.-]+\.#{domain.name})<\/TD>/).map do |column|
+          add_host(column[0])
         end
       end
     end