adding sqlite support, removing mysql required dependency

backend/model/sql/enitites/DirectoryEntity.ts

@@ -0,0 +1,39 @@
+import {Column, Entity, ManyToOne, OneToMany, PrimaryGeneratedColumn} from "typeorm";
+import {DirectoryDTO} from "../../../../common/entities/DirectoryDTO";
+import {PhotoEntity} from "./PhotoEntity";
+
+@Entity()
+export class DirectoryEntity implements DirectoryDTO {
+
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column({
+    length: 500
+  })
+  name: string;
+
+  @Column({
+    length: 500
+  })
+  path: string;
+
+
+  @Column('number')
+  public lastModified: number;
+  @Column('number')
+  public lastScanned: number;
+
+  @Column({type: 'smallint', length: 1})
+  public scanned: boolean;
+
+  @ManyToOne(type => DirectoryEntity, directory => directory.directories, {onDelete: "CASCADE"})
+  public parent: DirectoryEntity;
+
+  @OneToMany(type => DirectoryEntity, dir => dir.parent)
+  public directories: Array<DirectoryEntity>;
+
+  @OneToMany(type => PhotoEntity, photo => photo.directory)
+  public photos: Array<PhotoEntity>;
+
+}