in .tmTheme files the scope key defines how a element is highlighted:
name
HTML: Attribute
Unfortunately there doesn't seem to be any such comprehensive list.
However, if you press Shift+Ctrl+P in SublimeText 2, the status bar at the bottom of the screen will display a comprehensive list of all the scope keys that apply to the character immediately following your cursor position.
You can use this method to find the scope keys for anything you need from within SublimeText.