Fix vim modeline parsing
Fix vim modeline parsing

This is not really a bug, but rather an annoyance in case you use vim as
editor. :-)

vim wrongly takes the string ``ex: "apr"`` as [modeline
setting](http://vimdoc.sourceforge.net/htmldoc/options.html#modeline).

When opening the file this leads to

    "alias" 129L, 5485C
    Error detected while processing modelines:
    line   28:
    E518: Unknown option: "apr"

rolfschr/GSWL-ecosystem,rolfschr/GSWL-ecosystem,rolfschr/GSWL-ecosystem