It is useful to know today's cumulated Feeding amount.
Right now, this can be inferred from the "Feeding Amount" report,
but is not made readily available in the dashboard, where the
Feeding-related cards are the last Feeding and its method.
This adds a new card `Today's Feeding`, heavily based on "Today's Sleep".
This commit adds a placeholder image for Child objects (in the future, hopefully, photo uploads will be added) and reworks the Dashboard view to look better when more than one child is in the database. There are also some minor tweaks to the Child detail view and one new Gulp requirement to improve the flow of copying static image assets from apps.