Implement aborting search request while still typing

This commit adds support for aborting a pending search request while
a user is still typing a search term. This prevents a "result flash"
if the user is typing slowly.
Adds support for searching by a chat link
Add support for specifying the item count of a prize
Adjusted the development environment back to using SQLite

This commit adjusts the development environment back to using
SQLite as the database. It also cleans up the example configuration
file and the way that file is parsed/used.
Make ProdDataSourceConfig match DevDataSourceConfig
Adds basic interface for drawing administration (add items)
Completely restructures the templates

This commit cleans up the templates by introducing "layouts" to the
templating.
Fixes bug in index template
Merge branch 'develop' of https://github.com/jsumners/ice-lotto into develop