Package kernel-build-tools: Information

- Build for c8, c7.
- %karch restored (to allow rebuilding old tags and commits).

- kernel-macros: made %setup_kernel_module automatically add
  the usual {,Build}Requires for kernel-modules-*.
- kernel-macros: added for possible use in modules:
  + %kimage & %requires_kimage;
  + %update_kernel_modules_checkinstall
    (to produce a specific kind of checkinstall subpkg);
  + %setup_kernel_module_from_globals (split from %setup_kernel_module) for
    those who want to set %kversion and %krelease manually, without rpmquery).

- added %e2k support