! can: add auto-chunking for responses without content-length, fixes #455
+ can: proxy support, fixes #102
- added ConnectionType to HostConnectorSetup with the following options:
  - Direct
  - AutoProxied (default)
  - Proxied(proxyHost: String, proxyPort: Int)
- added Map[String, ProxySettings]to ClientConnectionSettings (proxy settings per scheme)
- HttpManager now calls connectorFor() which then delegates to hostConnectorFor() or proxiedConnectorFor() in case a proxy should be used. proxiedConnectorFor() returns a ProxiedHostConnector which fixes URIs and host headers and delegates to HttpHostConnector which connects to the proxy and is shared between ProxiedHostConnectors to the same proxy.
- added Uri.normalizedForHttp() and Uri.httpScheme() to DRY up the default scheme/port logic
- changed the param order in Uri.toEffectiveHttpRequestUri()
+ http: add method to supply default headers to HttpMessage
+ can: add defaultHeaders to HostConnectorSetup
Merge pull request #490 from 2beaucoup/ticket/102

Proxy Support, fixes #102
= can: small cleanups
Merge pull request #504 from 2beaucoup/small-cleanups

= can: small cleanups
Merge pull request #503 from jrudolph/i/455/autochunking-reponses-wo-length

! can: add auto-chunking for responses without content-length, fixes #455
! can: break out ServerSettings timeout settings into sub case class, closes #489
Merge pull request #506 from spray/ticket/498

! can: break out ServerSettings timeout settings into sub case class
! can: fix idle shutdown protocol for new ProxiedHostConnectors

Also renames the new `Http.ConnectionType` to `Http.ClientConnectionType`.
Smaller refactorings.
Merge pull request #505 from spray/wip/fix-spray-can-idle-shutdown

! can: fix idle shutdown protocol for new ProxiedHostConnectors
= io: register for OP_CONNECT only after the connection attempt was made, fixes #437

This is necessary because of at least two bugs in the JDK:
 * a channel is always connectable before the connection is attempted,
   and selecting for OP_CONNECT will instantly report connectable
 * even worse: after OP_CONNECT was reported true, also `finishConnect`
   will always return true, even if the connection wasn't yet established
Merge pull request #507 from jrudolph/i/437/unresponding-hosts-failure

= io: register for OP_CONNECT only after the connection attempt was made, fixes #437