Added conversion from ListIterator to ListConstIterator
Added conversion from ListIterator to ListConstIterator

PeeJay/ArduinoJson,AndreyAyres/ArduinoJson,janelia-arduino/ArduinoJson,hassanabidpk/ArduinoJson,weera00/ArduinoJson,peterpolidoro/ArduinoJson,0ddie/ArduinoJson,hemantsangwan/Arduino-Json,chuz/ArduinoJson,venusdharan/ArduinoJson,tirumalavan/ArduinoJson,firepick1/ArduinoJson,peterpolidoro/ArduinoJson,bblanchon/ArduinoJson,fayvlad/ArduinoJson,peterpolidoro/ArduinoJson,venkatarajasekhar/ArduinoJson,alyf80/ArduinoJson,janelia-arduino/ArduinoJson,fayvlad/ArduinoJson,firepick1/ArduinoJson,chuz/ArduinoJson,bblanchon/ArduinoJson,ELZo3/ArduinoJson,chuz/ArduinoJson,janelia-arduino/ArduinoJson,CanTireInnovations/ArduinoJson,naveensuryakumar/json,AndreyAyres/ArduinoJson,weera00/ArduinoJson,peterpolidoro/ArduinoJson,spotman/ArduinoJson,ELZo3/ArduinoJson,naveensuryakumar/json,alyf80/ArduinoJson,0ddie/ArduinoJson,janelia-arduino/ArduinoJson,firepick1/ArduinoJson,hemantsangwan/Arduino-Json,fayvlad/ArduinoJson,naveensuryakumar/json,venkatarajasekhar/ArduinoJson,hassanabidpk/ArduinoJson,CanTireInnovations/ArduinoJson,bblanchon/ArduinoJson,CanTireInnovations/ArduinoJson,alyf80/ArduinoJson,weera00/ArduinoJson,spotman/ArduinoJson,spotman/ArduinoJson,PeeJay/ArduinoJson,AndreyAyres/ArduinoJson,tirumalavan/ArduinoJson,venusdharan/ArduinoJson,hassanabidpk/ArduinoJson,ELZo3/ArduinoJson,venkatarajasekhar/ArduinoJson,hemantsangwan/Arduino-Json,tirumalavan/ArduinoJson,venusdharan/ArduinoJson,PeeJay/ArduinoJson