feature：完成通过数据库配置图床列表

lib/utils/sql.dart

@@ -0,0 +1,29 @@
+import './db_provider.dart';
+import '../model/base.dart';
+
+class Sql extends BaseModel {
+  
+  final String tableName;
+
+  Sql.setTable(this.tableName) : super(DbProvider.db);
+
+  // sdf
+  Future<List> get() async {
+    return await this.query(tableName);
+  }
+
+  String getTableName() {
+    return tableName;
+  }
+
+  Future<int> delete(String value, String key) async {
+    return await this
+        .db
+        .delete(tableName, where: '$key = ?', whereArgs: [value]);
+  }
+
+  Future<int> deleteAll() async {
+    return await this.db.delete(tableName);
+  }
+
+}