Remove rect texture extension usage and switch to GL_TEXTURE2D with 0-1 coords

indra/llrender/llgl.cpp

indra/llrender/llgl.h

indra/llrender/llrender.cpp

indra/llrender/llrender.h

indra/llrender/llrendertarget.cpp

indra/llrender/llshadermgr.cpp

indra/llrender/llshadermgr.h

indra/newview/app_settings/logcontrol.xml

.../newview/app_settings/shaders/class1/avatar/eyeballF.glsl

.../newview/app_settings/shaders/class1/avatar/eyeballV.glsl

...a/newview/app_settings/shaders/class1/deferred/SSAOF.glsl

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

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

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

indra/newview/app_settings/shaders/class1/deferred/cofF.glsl

...ewview/app_settings/shaders/class1/deferred/diffuseV.glsl

...iew/app_settings/shaders/class1/deferred/dofCombineF.glsl

...ings/shaders/class1/deferred/downsampleDepthNearestF.glsl

...pp_settings/shaders/class1/deferred/fullbrightShinyF.glsl

...a/newview/app_settings/shaders/class1/deferred/fxaaF.glsl