Thanks for this! 👍 I have added a demo to your pull request description, but you need to generate the dist files for it to work (run grunt) and add the new dist files.

:-D I need to figure out how to use grunt :-) ... I've never used it

You just need to run npm install to install all the dependencies and then npm run grunt.

I had to install grunt-cli and grunt-init globally and run the global "grunt" script.
"npm run grunt" was failing :-(

A few first remarks:

• you need to handle rightToLeft: true (left outer and right outer should be inverted)
• existing tests should be fixed
• new tests should be added to handle this new feature

Codecov Report

Merging #553 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff          @@
##           master   #553   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           1      1           
  Lines         972    990   +18     
=====================================
+ Hits          972    990   +18

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I need some guidance to understand what to do for code coverage.
It's the first time for me :-)

Ok, I think I've managed :-)
maybe with too much commits :-( sorry.

Let me know if you want other things

Great contribution! 👍 No worries for the commits, I'll squash and merge.

One last thing to be perfect: document the new option in the README and update the bower/npm versions to 6.4.0. Don't forget to run grunt to generate the dist files after the version update. 🙂

Ok, thanks. I'll do tonight (22:00 UK time)