cmd/codegen: add missing ImWchar return type (#51)

Also add missing ImGuiInputTextCallbackData.GetEventChar() method

Author: gucio321

cimgui_funcs.go

@@ -202,6 +202,7 @@ import "unsafe"
 		"char*":                    constCharReturnW,
 		"const char*":              constCharReturnW,
 		"const ImWchar*":           constWCharPtrReturnW,
+		"ImWchar":                  imWcharReturnW,
 		"float":                    floatReturnW,
 		"double":                   doubleReturnW,
 		"int":                      intReturnW,

cmd/codegen/gengo.go

@@ -39,6 +39,12 @@ func constWCharPtrReturnW() (returnType string, returnStmt string) {
 	return
 }
 
+func imWcharReturnW() (returnType string, returnStmt string) {
+	returnType = "ImWchar"
+	returnStmt = "return (ImWchar)(%s)"
+	return
+}
+
 func imVec4PtrReturnW() (returnType string, returnStmt string) {
 	returnType = "ImVec4"
 	returnStmt = "return newImVec4FromCPtr(%s)"