bootstrapping JDK

[Jonathan Gibbons]

There would appear to be an interesting issue regarding the ability to 
compile a modularized JDK, given that the compiler will defer to the 
module system to interpret the dependencies in module-info files, but 
the module system will not (yet) be available.

One possibly interesting approach would be to determine the minimal 
reasonable subset  of JDK sufficient to compile the module system 
code.   Once the module system code is available, the rest can be 
compiled using that code.  Thus the issue reduces to compiling those 
initial module system classes.

-- Jon