Tweak wording
Use `posn-actual-col-row' to determine the current col and row

Issue #136 WIP.

Reverting d21bb454dcfacda8808b596e4bca85a53a99eabf, for the most part,
http://lists.gnu.org/archive/html/emacs-devel/2014-08/msg00361.html.
Work around http://debbugs.gnu.org/18285

Closes #136
Fix the tests
company-buffer-lines: handle multiline display better

Improves #136.