Fix llParticleSystem to accept LSL variables and LSL constants in place

of the named constants for the rule selector.
Information provided by Snowcrash

OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs

@@ -5844,7 +5844,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
 
                 for (int i = 0; i < rules.Length; i += 2)
                 {
-                    switch ((int)rules.Data[i])
+                    switch (Convert.ToInt32(rules.Data[i]))
                     {
                         case (int)ScriptBaseClass.PSYS_PART_FLAGS:
                             prules.PartDataFlags = (Primitive.ParticleSystem.ParticleDataFlags)(uint)rules.GetLSLIntegerItem(i + 1);