DRTVWR-528, delete all unreferenced shader files, improve dev QoL

...settings/shaders/class1/deferred/avatarAlphaNoColorV.glsl

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

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

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

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

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

...p_settings/shaders/class1/deferred/shadowAlphaBlendF.glsl

...p_settings/shaders/class1/deferred/shadowAlphaBlendV.glsl

.../app_settings/shaders/class1/objects/indexedTextureF.glsl

...w/app_settings/shaders/class1/windlight/cloudShadowF.glsl

...w/app_settings/shaders/class1/windlight/cloudShadowV.glsl

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

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

...ettings/shaders/class3/deferred/depthToShadowVolumeG.glsl

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

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

...wview/app_settings/shaders/class3/deferred/genSkyShF.glsl

...wview/app_settings/shaders/class3/deferred/genSkyShV.glsl

...pp_settings/shaders/class3/deferred/pointShadowBlurF.glsl

.../newview/app_settings/shaders/class3/deferred/shVisF.glsl