[CMake] cdt4 generator and adding new source files from inside eclipse

[Dan Kegel]

I'm going over the checklist of whether cmake will meet
the needs of my eclipse users, and their first question
was what was the workflow for adding a new source
file.

I just tried the experiment of adding a .cpp file,
adding it to CMakeLists.txt, and clicking Build...
and the .o file showed up as it should have.  This
kind of surprised me, since I didn't re-run cmake.

Is the generator smart enough to notice the
changes to the CMake files and re-run cmake
with the same environment variables and options
as it was originally run with?  I kind of doubt it.

The cdt4 web page says
"When you edit your CMakeLists.txt file, you are recommended to delete
your project and reimport it."
Is it assuming that you've rerun cmake manually?