core/struct: check for capitalization instead of String.
core/struct: check for capitalization instead of String.

In opal String === Symbol, so we have to do this.

iliabylich/opal,opal/opal,fazibear/opal,jannishuebl/opal,Flikofbluelight747/opal,charliesome/opal,jgaskins/opal,castwide/opal,Mogztter/opal,opal/opal,suyesh/opal,gausie/opal,Mogztter/opal,wied03/opal,c42engineering/opal,Mogztter/opal,jannishuebl/opal,bbatsov/opal,iliabylich/opal,bbatsov/opal,wied03/opal,jgaskins/opal,kachick/opal,iliabylich/opal,Flikofbluelight747/opal,gabrielrios/opal,suyesh/opal,kachick/opal,Flikofbluelight747/opal,Ajedi32/opal,gausie/opal,merongivian/opal,kachick/opal,kachick/opal,catprintlabs/opal,catprintlabs/opal,merongivian/opal,catprintlabs/opal,jgaskins/opal,castwide/opal,gausie/opal,castwide/opal,c42engineering/opal,charliesome/opal,Ajedi32/opal,fazibear/opal,wied03/opal,gabrielrios/opal,Ajedi32/opal,merongivian/opal,bbatsov/opal,domgetter/opal,jannishuebl/opal,fazibear/opal,Mogztter/opal,opal/opal,c42engineering/opal,gabrielrios/opal,opal/opal,suyesh/opal,domgetter/opal