Support for importing AWS CloudFront log files

I have added support to allow import of Amazon CloudFront log files. It has been tested and it is working fine.
does the 0.101 means that it took 0.101 seconds to process the request? if so, maybe we could detect it in the regex as `<generation_time_milli>` ? Well if they are second instead of millisecond we'd need to add `<generation_time_seconds>`