add transferSize and decodedSize attributes
add step 18.2 to set transfer+decodedSize values
adding transferBodySize

Based on discussion at TPAC:
- adding transferBodySize
- renaming decodedSize to decodedBodySize

Above change allows direct comparison between payload size for
before+after any content-codings are aplied (e.g. gzip). In addition to
above, transferSize provides a way to account for other protocol
overhead.
transferBody > encodedBody
include HTTP overhead of same origin redirects in transferSize

Discussed on conf call on 12/11/04: including HTTP overhead is
consistent with redirect timing, which accounts for incurred cost for
same origin redirects.
Merge branch 'size' into gh-pages

Conflicts:
	index.html
fix nextHopProtocol anchor in processing model