[FEATURE] As a patient, I should be able to sign up

**How this feature request is related to a problem?**
To log in, the user needs to sign up. The patient should be able to see his/her profile/dashboard immediately signup.

**Solution we'd like**
The patient will be able to sign up without leaving the application. So, we adopt the password1 and password2 approach instead of sending an email to authenticate the patient.

The type of user should be passed as well. Whther Patient or Expert

**Alternatives we've considered**
Using an email to authenticate. Social media and other third party authentication.

**Additional context**

Trigger | Frontend | Backend (/api/signup)
-- | -- | --
Sign Up Page | Username | Username | Username | Username
  | Firstname | Firstname | Firstname | Firstname
  | Lastname | Lastname | Lastname | Lastname
  | Email | Email | Email | Email
  | Password1 |   | Password1 | Api token
  | Password2 |   | Password2 |  
  | Type |   | Type |