feature/BE-27 Account deletion API

[serdarakol]

No description provided.

[BElifb]

• Pulled the branch to local and tested.
• Postman gives

  {"Failure":"The password did not match!"}
  error, even though I entered the correct password.

• When I investigated the code, I saw that when checking the password, you're comparing the received string directly with user.password. Since we are keeping the encrypted versions of the passwords in the database, you should either encrypt the received password string and compare manually or use the password compare function provided (can't remember the exact name).
• Other than that the serializer for the swagger input was named "new_password", while your view function used "password".
• I fixed that and a few minor things about naming convertions.
• Finally, I though we agreed on, not completely deleting the user account but rather negating the active flag. So that we can have access to user information in case of a future conflict.

[BElifb]

• Just realized, serializer I changed was being used for another API as well. Created and switched to a new one.

[BElifb]

• Tested the updates, API works. I can approve the PR with a promise to revisit the inactivation issue after the milestone (instead of fully deleting user data).