UI: after successful registration user is just redirected to login page

[SagePtr]

• Gitea version (or commit ref): 9c354a5
• Git version: 2.7.5
• Operating system: any
• Database (use [x]):
  • PostgreSQL
  • MySQL
  • MSSQL
  • SQLite
• Can you reproduce the bug at https://try.gitea.io:
  • Yes (provide example URL) https://try.gitea.io/user/sign_up
  • No
  • Not relevant
• Log gist:

Description

After sucessful registration, user is just redirected to login page and should enter their login/password again.
There are no messages if registration was sucessful, user doesn't know whenever it worked.

User should be automatically logged in after registration or at least they shoud get message about successful registration.