Added an undefinded check so that the module doesn't crash if the property is not there.
Merge branch 'master' of https://github.com/Solid-Interactive/grasshopper-core-nodejs
++version - 0.13.31
Adding test for skip value
Merge branch 'kirby' of https://github.com/Solid-Interactive/grasshopper-core-nodejs into kirby
Added contributing collection to jekyll project.
Updated dev env docs.
Merge branch 'master' into kirby
Added line to index page.
Merging