The user guide should be kept with the makefiles to make it easier to keep it in sync.
The web pages should just refer to the TIP version of the manual for jdk8.

Basic principles:
* Keep top README and README-builds.html files as simple and terse as possible, refer to the user guide for detailed issues. Put more details in the user guide and keep it in common/docs. Don't pollute the upper level repository directory too much.
* Try to not duplicate information, or duplicate little and refer to more detailed docs.