added 64 bit linux version of wktohtml binary

bin/wkhtmltopdf

@@ -1,13 +1,19 @@
 #!/usr/bin/ruby
 
-if RUBY_PLATFORM =~ /linux/
-  executable = 'wkhtmltopdf_linux_386'
-elsif RUBY_PLATFORM =~ /darwin/
-  executable = 'wkhtmltopdf_darwin_386'
-else
-  raise "Invalid platform. Must be running linux or intel-based Mac OS."
+executable = case RUBY_PLATFORM
+  when /64.*linux/
+    'wkhtmltopdf_linux_amd64'
+  when /linux/
+    'wkhtmltopdf_linux_386'
+  when /darwin/
+    'wkhtmltopdf_darwin_386'
+  else
+    raise "Invalid platform. Must be running linux or intel-based Mac OS."
 end
 
+arguments = $*.map { |x| x.include?(' ') ? "'" + x + "'" : x }
+
 executable = File.join(File.dirname(__FILE__), executable)
-system(executable + " " + $*.join(" "))
+r = system(executable + " " + arguments.join(" "))
 
+exit r ? 0 : 1

bin/wkhtmltopdf-binary.rb

@@ -0,0 +1,2 @@
+# Having this file, which matches the name of the gem,
+# is required for the gem to be installed and called properly.