feat: add struct and list data type (#277)

* feat: add struct and list data type

* type extensions

* feat: extend column type

* chore: rename fields

* add value enum item

* feat: add value

* refactor: item->items

* feat: use single ListValue/StructValue for Row and Column

proto/greptime/v1/column.proto

@@ -17,6 +17,7 @@ syntax = "proto3";
 package greptime.v1;
 
 import "greptime/v1/common.proto";
+import "greptime/v1/row.proto";
 
 option go_package = "github.com/GreptimeTeam/greptime-proto/go/greptime/v1";
 option java_outer_classname = "Columns";
@@ -58,7 +59,11 @@ message Column {
     repeated int64 interval_day_time_values = 25;
     repeated IntervalMonthDayNano interval_month_day_nano_values = 26;
     repeated Decimal128 decimal128_values = 31;
+
+    repeated ListValue list_values = 40;
+    repeated StructValue struct_values = 41;
   }
+
   // The array of non-null values in this column.
   //
   // For example: suppose there is a column "foo" that contains some int32