Add Options and Head to RequestBuilding
routing: fix `optionalCookie` directive leaking MissingCookieRejection
routing: add `cancelRejection` directive, improve `authorize` and `respondWithMediaType` directives
routing: extend and improve `respondWithDirectives`
Merge pull request #294 from vjousse/request-building-options-head

Add Options and Head to RequestBuilding
add multiple arguments to setCookie and deleteCookie directives
Merge pull request #295 from andrebeat/feature-cookie-directive

Add multiple arguments to setCookie and deleteCookie directives
http: tiny tweaks in Uri.Query
sbt: upgrade to Akka 2.1.4
can: fix bug in message parser (chunk parser), closes #292
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Travis CI: Tune JVM args of sbt (Xss3M)

Override default thread stack size (3M instead of 6M)