Update 1.21

Mayor new content. Update 1.21 contains:

-2 new game modes (headhunt and domination)

-6 new guns (harpune gun, Mendoza, MP-40, Krtek, HS-12, M-37)

-6 new perks (tactical nuke, red dot sight, ACOG, laser beam, underslung grenade launcher, C4 belt)

-new sprites for ADS.

-Fleshed out loading screen added.

-Map changes to "Roadkill" and "Chateau".

-Pause screen (Back-button).

-Slight changes to all maps. Balance changes.