feat: create table through GRPC interface (#224)

* feat: create table through GRPC interface

* move `CreateExpr` `oneof` expr of `AdminExpr` in `admin.proto`, and implement the admin GRPC interface

* add `table_options` and `partition_options` to `CreateExpr`

* resolve code review comments

Co-authored-by: luofucong <luofucong@greptime.com>

src/table/src/requests.rs

@@ -24,6 +24,7 @@ pub struct CreateTableRequest {
     pub schema: SchemaRef,
     pub primary_key_indices: Vec<usize>,
     pub create_if_not_exists: bool,
+    pub table_options: HashMap<String, String>,
 }
 
 /// Open table request