Content: ACF Expression2 Extension

Added some E2 functions relating to various ACF entities.
-Search "acf" in e2helper for a complete list and description of functions.
-Includes the convar "sbox_acf_e2restrictinfo" that restricts certain functions (generally those that return sensitive data) to usage on owned entities, preventing abuse during battles. Defaults to 1 (restricted).
-Functions that change values, e.g. gearbox shifting, are permanently restricted to owned entities.