rename environment variables

src/app/app.component.ts

.../filevisualizer/services/image-file-visualizer.service.ts

...ed/filevisualizer/services/mol-file-visualizer.service.ts

...levisualizer/services/ng2-xs-viewer-visualizer.service.ts

...zer/services/pdf-file-visualizer-with-tool-bar.service.ts

...ed/filevisualizer/services/pdf-file-visualizer.service.ts

...ed/filevisualizer/services/sme-file-visualizer.service.ts

.../filevisualizer/services/sound-file-visualizer.service.ts

...d/filevisualizer/services/text-file-visualizer.service.ts

...lizer/services/video-classical-file-visualizer.service.ts

.../filevisualizer/services/video-file-visualizer.service.ts

src/environments/environment.defaults.model.ts

src/environments/environment.defaults.ts