Timeout value too low and no useful error message

[mattblaha]

I was running into the same "Unable to access" errors other users have reported. I eventually realized that the 1000 ms timeout value in phantom-scrape.js was just too low for any page I was hitting and my internet connection.

I'd like to bump the timeout value to at least 5000 ms, and add a handler so the app returns a more useful message.

[mattblaha]

I realized this patch can sometimes cause a pretty serious problem. Since the main webapp reads stdout from phantom-scrape.js, writing the error message with console.log() can cause the main app to read invalid JSON. One unimportant resource timing out in a large page will cause an error in the webapp even if everything else works and the results are what we want. The valid JSON will be there, but the parser won't be able to handle the error message printed above it.

I switched it to write to stderr, which fixes the problem, though I'm not sure this is the best way to do that.

It's the best way I could find after reading this discussion:

ariya/phantomjs#10150