Fix #779: use the default chart type for new series
Fix #779: use the default chart type for new series

imsally/redash,rockwotj/redash,akariv/redash,getredash/redash,M32Media/redash,EverlyWell/redash,guaguadev/redash,useabode/redash,rockwotj/redash,denisov-vlad/redash,guaguadev/redash,vishesh92/redash,alexanderlz/redash,crowdworks/redash,getredash/redash,EverlyWell/redash,44px/redash,pubnative/redash,moritz9/redash,hudl/redash,pubnative/redash,M32Media/redash,rockwotj/redash,44px/redash,chriszs/redash,ninneko/redash,guaguadev/redash,crowdworks/redash,stefanseifert/redash,amino-data/redash,getredash/redash,useabode/redash,ninneko/redash,amino-data/redash,easytaxibr/redash,vishesh92/redash,ninneko/redash,akariv/redash,44px/redash,akariv/redash,M32Media/redash,chriszs/redash,stefanseifert/redash,imsally/redash,easytaxibr/redash,hudl/redash,pubnative/redash,alexanderlz/redash,guaguadev/redash,44px/redash,amino-data/redash,moritz9/redash,vishesh92/redash,hudl/redash,moritz9/redash,akariv/redash,easytaxibr/redash,guaguadev/redash,useabode/redash,easytaxibr/redash,denisov-vlad/redash,pubnative/redash,akariv/redash,alexanderlz/redash,hudl/redash,imsally/redash,denisov-vlad/redash,moritz9/redash,stefanseifert/redash,stefanseifert/redash,rockwotj/redash,amino-data/redash,ninneko/redash,easytaxibr/redash,chriszs/redash,ninneko/redash,getredash/redash,denisov-vlad/redash,EverlyWell/redash,stefanseifert/redash,EverlyWell/redash,chriszs/redash,imsally/redash,getredash/redash,crowdworks/redash,denisov-vlad/redash,M32Media/redash,crowdworks/redash,pubnative/redash,vishesh92/redash,useabode/redash,alexanderlz/redash