= can: improve reference.conf inline docs
= http: refactor HttpHeaderSpec for clarity and reduced compiler stack pressure
= http: parser not accepting media-ranges w/ subtype starting w/ `*`, closes #554
= can & http: allow custom Content-Type and Content-Length headers when required, closes #543

Also prepares the spray-can RequestRenderingComponent for chunkless request streaming.
Merge pull request #556 from spray/ticket/543

= can & http: allow custom Content-Type and Content-Length headers when ...
+ servlet: servlet: add `illegal-header-warnings` setting in analogy to spray-can, closes #553
Merge pull request #557 from spray/ticket/554

Ticket/554
Merge pull request #558 from spray/ticket/553

+ servlet: servlet: add `illegal-header-warnings` setting in analogy to ...
! io: abort connection on idle-timeout, fixes #539

Also make sure idle-timeout only triggers if no write is currently
pending.
Merge pull request #552 from jrudolph/i/539/abort-on-idle-timeout

Fix 539 and fix idle-timeouts from firing during long pending writes
= can: prevent server-side idle-timeout setting < 1 second