Add module information to all header files.
Update all header file documentations to briefly say what they are, and
to use the javadoc format so the brief actually gets included into the
doxygen documentation.
Remove \file from implementation files, in order to not repeat the info
from the header files.
Add files under strategies and tools to Doxygen and update the Doxygen
settings to be just plain better.
Make README be the main page of Doxygen documentation.
