NEWS: untabified and added file local variables block

NEWS: untabified and added file local variables block

Changed all tabs to 8 spaces (M-x untabify over region of the
whole file).

Now this looks uniformly on all viewers (using fixed-width font)
and the observed difference between this "source" file and markdown
generated html output on browser window is smaller. In markdown to
html conversions tab and 8 spaces indents differently.

Also the "Local variables:" block added to the end of this file
attempts to ensure tabs are always expanded; whether the used editor
is Emacs or Vi.