Simulator support: adding svg.filter api
Simulator support: adding svg.filter api

Microsoft/pxt,switch-education/pxt,switchinnovations/pxt,playi/pxt,switch-education/pxt,switchinnovations/pxt,Microsoft/pxt,switchinnovations/pxt,Microsoft/pxt,switch-education/pxt,switchinnovations/pxt,Microsoft/pxt,Microsoft/pxt,playi/pxt,switch-education/pxt,switch-education/pxt,playi/pxt,playi/pxt