Add customization hooks to resteasy-netty NettyJaxrsServer

This changeset adds customization hooks for ChannelHandler and channel options
to NettyJaxrsServer. It enables users to customize Netty's ServerBootstrap in
a limited way which can be used to add logging, transparent compression handling,
and other things.
Add customization hooks to resteasy-netty4 NettyJaxrsServer

This changeset adds customization hooks for ChannelHandler and ChannelOptions
to NettyJaxrsServer. It enables users to customize Netty's ServerBootstrap in
a limited way which can be used to add logging, transparent compression handling,
and other things.
Merge pull request #586 from joschi/494-customize-serverbootstrap

Customize Netty ServerBootstrap (fixes #494)