Intercept requests

[royallthefourth]

When active, check for the current request's domain in the domain list. If present, replace it with whatever record is in the config.

• onBeforeRequest: check for presence of requestDetails.url in storage.local
• If present, add requestId: originalUrl pair to storage
• Return object with redirectUrl
• onBeforeSendHeaders: if requestId is present in storage, reset host header to value stored for this requestId