Integrate new server authentication to client

Changes:
- Use server authentication REST API
- Log in automatically after registration
- Store token in localStorage
- Give feedback to user if registration or login fails

GitLab: #75
Change-Id: Ib90e5b911621567c6825af5e275920d703cdfe88
diff --git a/client/.env.development b/client/.env.development
index 2accbba..6d453cd 100644
--- a/client/.env.development
+++ b/client/.env.development
@@ -1 +1,2 @@
 ESLINT_NO_DEV_ERRORS=true
+VITE_API_URL=http://localhost:5000
\ No newline at end of file