Added demo level

.gitignore

build/demos/levels/transparent/transparent.ent

build/demos/levels/transparent/transparent.lvl

build/demos/materials/tp/tp_combineglass001a.mtl

build/demos/materials/tp/tp_gate_door_glass.mtl

build/demos/materials/tp/tp_glasswindowbreak070a.mtl

build/demos/materials/tp/tp_sga_window_center_up.mtl

build/demos/meshes/transparent/base.dse

build/demos/meshes/transparent/box1.dse

build/demos/meshes/transparent/box2.dse

build/demos/meshes/transparent/box3.dse

build/demos/meshes/transparent/plane1.dse

build/demos/meshes/transparent/plane2.dse

build/demos/textures/tp/tp_combineglass001a.dds

build/demos/textures/tp/tp_combineglass001a.tga

build/demos/textures/tp/tp_gate_door_glass.dds

build/demos/textures/tp/tp_gate_door_glass.tga

build/demos/textures/tp/tp_gate_door_glass_normal.dds

build/demos/textures/tp/tp_gate_door_glass_normal.tga

build/demos/textures/tp/tp_glasswindowbreak070a.dds