Support errLogToConsole from gulp-sass

[leevigraham]

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. :)

[sindresorhus]

Thanks, but I'm not interested in adding more options. This should be fixed at gulp core level: gulpjs/gulp#359

You're supposed to listen to errors on the stream and handle them the way you want. See the gulp docs.

I've added some logging as people don't seem to get the current gulp error handling.

[leevigraham]

Fair enough.