Improvement: Added help text for --vimemu flag.

Added some more output at the end of the vim-emu
installation to make it easier to understand.

This is now fully compatible to the emulator
documentation in the wiki:
https://osm.etsi.org/wikipub/index.php/VIM_emulator#Usage_example



Change-Id: I3cb49ac0de4bf5ecf2516c3f1242901bc14541a8
Signed-off-by: peusterm <manuel.peuster@uni-paderborn.de>