Improve formatting, primarily by:
* Adding links to relevant commands, properties, generators, and so on.
* Converting code, symbols, paths, and so on to fixed-width fonts.
* Hard wrapping lines to 80 characters or less.
Refactor edit_cache tool selection to ask each global generator for its
preference. Teach the Ninja generator to always use cmake-gui because
Ninja by design cannot run interactive terminal dialogs like ccmake.
Teach the Makefile generator to use cmake-gui when also using an "extra"
generator whose IDE has no terminal to run ccmake, and otherwise fall
back to CMAKE_EDIT_COMMAND selection for normal Makefile build systems.
James Johnston
Brad King
Kitware Robot