runastyle: Ignore user's default options file

If we pass --options=none to astyle, it ignores the user's
default options file, and only uses the command line parameters.
This way, if the user has a default options file, it won't conflict
with the style set by the script.
Merge pull request #219 from crumblingstatue/astyle-options-none

runastyle: Ignore user's default options file