Clean up repeated access of the gbuffer in shaders

...ew/app_settings/shaders/class1/deferred/deferredUtil.glsl

...wview/app_settings/shaders/class1/deferred/materialF.glsl

...app_settings/shaders/class1/deferred/multiSpotLightF.glsl

...ew/app_settings/shaders/class1/deferred/softenLightF.glsl

...view/app_settings/shaders/class1/deferred/spotLightF.glsl

.../newview/app_settings/shaders/class1/deferred/waterF.glsl

...app_settings/shaders/class2/deferred/multiSpotLightF.glsl

...ew/app_settings/shaders/class2/deferred/softenLightF.glsl

...view/app_settings/shaders/class2/deferred/spotLightF.glsl

...ew/app_settings/shaders/class3/deferred/deferredUtil.glsl

...app_settings/shaders/class3/deferred/multiSpotLightF.glsl

...ew/app_settings/shaders/class3/deferred/softenLightF.glsl

...view/app_settings/shaders/class3/deferred/spotLightF.glsl