added basic skeleton for cross-browser chart testing
added basic skeleton for cross-browser chart testing

ThuyNTran/datawrapper,motherjones/datawrapper,washingtonpost/datawrapper,rubensfernando/datawrapper,robmcloughlin/Insights,plusgut/datawrapper,elaOnMars/datawrapper,elaOnMars/datawrapper,datafunk/datawrapper,devinit/datawrapper,motherjones/datawrapper,kendrick-k/datawrapper,grepman/datawrapper,motherjones/datawrapper,kendrick-k/datawrapper,shelsonjava/datawrapper,ThuyNTran/datawrapper,plusgut/datawrapper,rubensfernando/datawrapper,washingtonpost/datawrapper,datafunk/datawrapper,shelsonjava/datawrapper,datafunk/datawrapper,shelsonjava/datawrapper,robmcloughlin/Insights,devinit/datawrapper,devinit/datawrapper,devinit/datawrapper,washingtonpost/datawrapper,elaOnMars/datawrapper,grepman/datawrapper,qqming113/datawrapper,devinit/datawrapper,annelisebouyer/datawrapper,washingtonpost/datawrapper,kendrick-k/datawrapper,plusgut/datawrapper,plusgut/datawrapper,rubensfernando/datawrapper,motherjones/datawrapper,washingtonpost/datawrapper,kendrick-k/datawrapper,ThuyNTran/datawrapper,robmcloughlin/Insights,kendrick-k/datawrapper,datafunk/datawrapper,elaOnMars/datawrapper,robmcloughlin/Insights,grepman/datawrapper,annelisebouyer/datawrapper,qqming113/datawrapper,rubensfernando/datawrapper,kendrick-k/datawrapper,annelisebouyer/datawrapper,datafunk/datawrapper,qqming113/datawrapper,shelsonjava/datawrapper,ThuyNTran/datawrapper,annelisebouyer/datawrapper,robmcloughlin/Insights,elaOnMars/datawrapper,qqming113/datawrapper,annelisebouyer/datawrapper,motherjones/datawrapper,qqming113/datawrapper,elaOnMars/datawrapper,rubensfernando/datawrapper,grepman/datawrapper,ThuyNTran/datawrapper,grepman/datawrapper,grepman/datawrapper,devinit/datawrapper,shelsonjava/datawrapper,annelisebouyer/datawrapper,shelsonjava/datawrapper,datafunk/datawrapper,washingtonpost/datawrapper,ThuyNTran/datawrapper,qqming113/datawrapper,motherjones/datawrapper