Add stub of patient edit page

- Needs better inputs (date, textarea, placeholders)
- Needs validation and real submit handler

Also:
- Add logic in main app component to redirect if trying to view a
  patient that does not exist, or trying to edit a patient that user
  doesn't own
- Add debug console logs to see changes in main app states
Add textarea, date input, placeholders

- Update SimpleForm and InputGroup
- Use in PatientEdit
Introduce validation mixin and patient service
Add more validation to patient edit

Introduce Moment.js
Add patient put method to api service

And use it for PatientEdit