Make the ParticleEmitter's period & emission timers editable to be able to reset them before saving an object prefab.

Engine/Graphics/ParticleEmitter.cpp

@@ -142,8 +142,8 @@ void ParticleEmitter::RegisterObject(Context* context)
     ACCESSOR_ATTRIBUTE(ParticleEmitter, VAR_FLOAT, "Draw Distance", GetDrawDistance, SetDrawDistance, float, 0.0f, AM_DEFAULT);
     ACCESSOR_ATTRIBUTE(ParticleEmitter, VAR_FLOAT, "Shadow Distance", GetShadowDistance, SetShadowDistance, float, 0.0f, AM_DEFAULT);
     ACCESSOR_ATTRIBUTE(ParticleEmitter, VAR_FLOAT, "Animation LOD Bias", GetAnimationLodBias, SetAnimationLodBias, float, 1.0f, AM_DEFAULT);
-    ATTRIBUTE(ParticleEmitter, VAR_FLOAT, "Period Timer", periodTimer_, 0.0f, AM_FILE | AM_NOEDIT);
-    ATTRIBUTE(ParticleEmitter, VAR_FLOAT, "Emission Timer", emissionTimer_, 0.0f, AM_FILE | AM_NOEDIT);
+    ATTRIBUTE(ParticleEmitter, VAR_FLOAT, "Period Timer", periodTimer_, 0.0f, AM_FILE);
+    ATTRIBUTE(ParticleEmitter, VAR_FLOAT, "Emission Timer", emissionTimer_, 0.0f, AM_FILE);
     ACCESSOR_ATTRIBUTE(ParticleEmitter, VAR_VARIANTVECTOR, "Particles", GetParticlesAttr, SetParticlesAttr, VariantVector, Variant::emptyVariantVector, AM_FILE | AM_NOEDIT);
     ACCESSOR_ATTRIBUTE(ParticleEmitter, VAR_VARIANTVECTOR, "Billboards", GetBillboardsAttr, SetBillboardsAttr, VariantVector, Variant::emptyVariantVector, AM_FILE | AM_NOEDIT);
 }