clean + code refactoring

src/app/attachment/controllers/AttachmentController.php

src/frontend/app/annotation/annotation.component.html

src/frontend/app/annotation/annotation.component.spec.ts

src/frontend/app/annotation/annotation.component.styl

src/frontend/app/annotation/annotation.component.ts

src/frontend/app/app.component.html

src/frontend/app/app.component.ts

src/frontend/app/app.module.ts

src/frontend/app/canvas-drag/canvas-drag.component.html

src/frontend/app/canvas-drag/canvas-drag.component.spec.ts

src/frontend/app/canvas-drag/canvas-drag.component.styl

src/frontend/app/canvas-drag/canvas-drag.component.ts

src/frontend/app/document/document.component.html

src/frontend/app/document/document.component.ts

src/frontend/app/drawer/drawer.component.html

src/frontend/app/drawer/drawer.component.ts

src/frontend/app/pad/pad.component.html

src/frontend/app/pad/pad.component.ts

src/frontend/app/service/signatures.service.ts

src/frontend/app/sidebar/sidebar.component.html