Refactor registration and login and improve routing

Changes:
- Improve registration and login pages
- Extract Home component from App.tsx file into its own
- Make Home component display registration or login
- Extract routes from App component and refactor routing

GitLab: #12
Change-Id: I68b01890781308282072b6dcf5e6df0d54837b4a
diff --git a/client/src/utils/constants.ts b/client/src/utils/constants.ts
index 06d1b92..341622f 100644
--- a/client/src/utils/constants.ts
+++ b/client/src/utils/constants.ts
@@ -15,7 +15,7 @@
  * License along with this program.  If not, see
  * <https://www.gnu.org/licenses/>.
  */
-export const jamiUsernamePattern = '^[a-zA-Z0-9-_]{3,32}$';
+export const jamiUsernamePattern = /^[a-zA-Z0-9-_]{3,32}$/;
 
 export const inputWidth = 260;