Support errLogToConsole from gulp-sass

https://www.npmjs.org/package/gulp-sass has a errLogToConsole option:

If you pass errLogToConsole: true into the options hash, sass errors will be logged to the console instead of generating a gutil.PluginError object. Use this option with gulp.watch to keep gulp from stopping every time you mess up your sass.

I've implemented the same functionality in this PR. 

First gulp plugin contribution so the implementation style might not be correct. :)