adds "parts" button for pxt-arduino
adds "parts" button for pxt-arduino

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