Improve Javadoc of ChannelPipeline

- Fixes #1226
[maven-release-plugin] prepare release netty-4.0.0.CR7
[maven-release-plugin] prepare for next development iteration
Add javadocs
Remove un-used method parameter
SPDY: SpdyHeaderBlockDecoder should not discard input data
[#1489] Correctly handle channelReadSuspended and channelWritabilityChanged in CombinedChannelDuplexHandler
[#1500] Remove @deprecated methods
Fix compilation errors
Only log about not avaible JavaAssist in debug level
Less confusing log messages for system properties

- Fixes #1502
Add missing sanity check for DefaultChannelHandlerContext.write(...)
Fix a bug in MessageList.add(T[])

- where it uses incorrect source index while iteration
Use higher maxMessagesPerRead as default for ServerChannels

- Fixes #1493
[maven-release-plugin] prepare release netty-4.0.0.CR8
[maven-release-plugin] prepare for next development iteration
Improve performance of encodeHeader
[#1501] Fix NPE which could accour if ChannelOutboundBuffer.fail(..) triggered another call to ChannelOutboundBuffer.fail(...)
[#1501] Fix NPE correctly which could accour if ChannelOutboundBuffer.fail(..) triggered another call to ChannelOutboundBuffer.fail(...)
Better explanation of reentrance issue of ChannelOutboundBuffer