Update highstock, fix various PHP warnings, and create a recipe import tool.

This will update Highstock to the latest version (1.3.4). This fixes the odd coin image in the upper left corner of graphs that almost entirely obscured.

Also fixed some PHP warnings that appeared when in debug mode.

Also created a a tool to import recipes from the official GW2 API.
Used like:
php tools/create-recipe-map.php > recipemap.json
php tools/import-recipe-map.php recipemap.json