Add a generic --method command to set a method in HTTP Requests.

Add supplementary --body-data and --body-file commands to send BODY Data.

Signed-off-by: Darshit Shah <darnir@gmail.com>
NEWS: cite --method.
warc: Follow the guidelines for metadata records

Do not use the same UUID for the manifest and arguments records.
Write the manifest as a metadata record, not as a resource.
doc: add documentation for mega dot style.