Bottom navbar for mobile (#51)

* - implemented Botton navbar for mobile devices
- Also made navbar conditional to render only when its on of the paths in the navbar

* - Added text to the mobile bottom bar
- Changed /downloads Path title to Downloads
- Added conditional paddingBottom when on mobile

* Made the Sidebar Seperate component used just for Non-Mobile Devices

* Added the main Material UI System package

* Extracted the Bottom Navbar into a seperate component

* updated the mui dependencies

src/App.tsx

@@ -92,6 +92,7 @@ export default function App() {
                             style={{
                                 marginTop: theme.spacing(8),
                                 marginLeft: isMobileWidth ? '' : theme.spacing(8),
+                                marginBottom: isMobileWidth ? theme.spacing(8) : '',
                                 width: 'auto',
                                 overflow: 'auto',
                             }}