PhantomJS: Version and remote actions should be recorded

[chfoo]

For WARC files, Wpull should record the version of PhantomJS in the warcinfo and remote actions, ie "Scrolled 6 times", should be recorded through the main logging as INFO or perhaps a dedicated log.

[chfoo]

It might make sense that WARC metadata type record is used to hold the actions as a content type application/json. The main logs should also contain the actions textually. The actual snapshot resources should contain the WARC-Concurrent-To field pointing to the metadata record. Both resource and metadata records should keep the same URI (currently urn:X-wpull:snapshot?url=http://example.com).