fix job hanging on bad camel url

it turns out that some remote camel urls will cause an application to
 hang when calling consume() from CamelService.  I changed this to
 consumeWait().  No if nothing comes back in 15 seconds,
 the app will continue instead of hanging.  Additionally if
 nothing comes back an exception is thrown.  This should still work
 with an empty directory.

 Issue #7
Merge pull request #12 from metridoc/fix-bad-url-hanging

fix job hanging on bad camel url