Fix two bugs in the http libraries:

1) Re-add 443 to the common ssl ports (it was accidentally removed in an earlier patch)
2) If the header doesn't return the number of pipelined requests to perform, default to 40 instead of leaving it nil

nselib/http.lua

@@ -280,6 +280,9 @@ local function getPipelineMax( response )
     if response.header and response.header.connection ~= "close" then
       if response.header["keep-alive"] then
         local max = string.match( response.header["keep-alive"], "max\=(%d*)")
+        if(max == nil) then
+          return 40
+        end
         return max
       else return 40 end
     end