Fix recorder embedded resources fetching.

* Remove white = WhiteList() if filter strategy is disabled.
* Parse response body for embedded resources instead of request body.
* Copy embedded resources in resulting RequestElement on redirection filtering.
* Fix splitWhen function : split Seq when predicate is true, not false.
* Use Html content type to split requests instead of embedded resources presence.
Merge pull request #1689 from blemale/bugfix/fix-recorder-html-fetching

Fix recorder embedded resources fetching