Add PermissionModule and GroupsModule

Both currently contain only the database entities, taken from the schema.

Signed-off-by: David Mehren <git@herrmehren.de>

src/groups/group.entity.ts

@@ -0,0 +1,23 @@
+import { Column, Entity, PrimaryGeneratedColumn } from 'typeorm/index';
+
+@Entity()
+export class Group {
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column({
+    unique: true,
+  })
+  name: string;
+
+  @Column()
+  displayName: string;
+
+  /**
+   * Is set to denote a special group
+   * Special groups are used to map the old share settings like "everyone can edit"
+   * or "logged in users can view" to the group permission system
+   */
+  @Column()
+  special: boolean;
+}