Better tracking of failed requests + logging context exclude

[ikreymer]

• add --logExcludeContext for log contexts that should be excluded (while --logContext specifies which are to be included)
• enable 'recorderNetwork' logging for debugging CDP network
• create default log context exclude list (containing: screencast, recorderNetwork, jsErrors), customizable via --logExcludeContext

recorder: Track failed requests and include in pageinfo records with status code 0

• cleanup cdp handler methods
• intercept requestWillBeSent to track requests that started (but may not complete)
• fix shouldSkip() still working if no url is provided (eg. check only headers)
• set status to 0 for async fetch failures
• remove responseServedFromCache interception, as response data generally not available then, and responseReceived is still called
• pageinfo: include page requests that failed with status code 0, also include 'error' status if available.
• ensure page is closed on failure
• ensure pageinfo still written even if nothing else is crawled for a page
• track cached responses, add to debug logging (can also add to pageinfo later if needed)

tests: add pageinfo test for crawling invalid URL, which should still result in pageinfo record with status code 0

bump to 1.0.0-beta.7

[tw4l]

Very nice! Tested and working well. The pages.jsonl file produced pre-WACZ generation includes all of the pages now. Once we switch to js-wacz and use the existing pages files, we should be all good!