Shows the items that a research unlocks.
The list of buttons to be displayed on this page.
Supplies the buttons to be displayed on this page.
The title of this page, displayed at the top of the GUI when the page is open.
Created the page for the given player.
Returns a page containing the header (the top row of the page) and a section for the items to go.
Opens the GUI for a player.
Should the page be displayed to said player? If not it won't be added to the button list