Get single child data from database

Get child from database via route parameter. Display name, avatar and hardcoded points from controller. Add methods for getting name and avatar. Throw 404 if not found.

Issue #23.
Add placeholder avatars
Get kid placeholder image

Issue #23. Close #14.
Make single child page title dynamic

Issue #23.
Add log form rendering logic

Issue #25.
Save log action

Close #25.
Make list of action dynamic in child page

Close #23.
Merge branch 'dynamic-single-child'

* dynamic-single-child:
  Make list of action dynamic in child page
  Save log action
  Add log form rendering logic
  Make single child page title dynamic
  Get kid placeholder image
  Add placeholder avatars
  Get single child data from database