Added better default value handing for icon module
Added better default value handing for icon module

gionkunz/chartist-js,cr3ative/chartist-js,chartist-js/chartist,chartist-js/chartist,gionkunz/chartist-js,chartist-js/chartist,cr3ative/chartist-js,hansmaad/chartist-js,hansmaad/chartist-js