Add a note about filename expansions
Add a note about filename expansions

This is mentioned in
[emacs-ycmd](https://github.com/abingham/emacs-ycmd#quickstart)
documentation as well, but it doesn't hurt to have it here as well.

tsonntag/dotemacs,tsonntag/dotemacs,tsonntag/dotemacs,tsonntag/dotemacs