todo: Add /todo.json endpoint
todo: Add /todo.json endpoint

Add a new endpoint for /todo view with the same information as on the
normal /todo page for use of automation.

archlinux/arch-security-tracker,archlinux/arch-security-tracker,anthraxx/arch-security-tracker,anthraxx/arch-security-tracker,anthraxx/arch-security-tracker,jelly/arch-security-tracker,jelly/arch-security-tracker