Describe handling of invalid values for SETTINGS_ENABLE_PUSH.
refine approach to hop-by-hop headers; addresses #21.
Merge pull request #372 from http2/hop

refine approach to hop-by-hop headers; addresses #21.
Adding initial text for connection coalescing for #359.
update XSLTs, tune metadata
remove unneeded XML elements
Denial of service at connect time.  Closes #343.
Merge pull request #369 from hruellan/settings

Describe handling of invalid values for SETTINGS_ENABLE_PUSH.
Fixes #354.
Updating issues.