Do not drop sys_boot

This fixes #2391
- Fix the attach examples according to the new attach behavior
- Add the option of adding the user to docker's group and avoid the usage of "sudo" before each command
- Included the sudo alternative as an example_header
Add warning about SYS_BOOT capability with pre-3.4 kernels and pre-0.8 LXC.
Add more depth to the upstart example in host_integration.rst

I found that the original example wasn't starting the docker container when docker is started.  So, I modified it using information I found from https://groups.google.com/forum/#!msg/docker-user/OWz8EOpiXuo/L_uxGFQuYlkJ

Also, upstart wasn't starting docker if it wasn't running ahead of time.  So, I added a change to the docker upstart script to solve this.
Clean up sphinx syntax, upgrade http markup package, minor link changes, update intro.
Move integration tests to integration/, expose missing public methods in the core
Integration tests: remove dependency on private APIs
gofmt
Remove deprecated tags_test.go
fix Integration tests
move TestMount to integration
Split auth tests between unit tests and integration tests
Move iptables test to integration tests
path needs to be specified to 'docker build' command

current folder '.' appended as a path
port published explicitly (for docker 0.6.6)

port 5984 to couchdb needs to be published explicitly in docker version 0.6.6
Fix typos, add links, streamline content of #2592
bring back tests about LXCConfig
Fix tmp dir never cleanup
Re-enable api integration tests using only public remote API.