add two-arg seed_for_storage variant

Author: marius311

src/sampling.jl

@@ -193,7 +193,7 @@ function sample_joint(
     end
 
     # seed
-    @everywhere seed_for_storage!($storage)
+    @everywhere seed_for_storage!((Array,$storage))
 
     # initialize chains
     if (filename != nothing) && isfile(filename)

src/util.jl

@@ -353,13 +353,16 @@ end
 
 @doc doc"""
     seed_for_storage!(storage[, seed])
+    seed_for_storage!((storage1, storage2, ...)[, seed])
     
 Set the global random seed for the RNG which controls `storage`-type. 
 """
 seed_for_storage!(::Type{<:Array}, seed=nothing) = 
     Random.seed!((seed == nothing ? () : (seed,))...)
 seed_for_storage!(storage::Any, seed=nothing) = 
     error("Don't know how to set seed for storage=$storage")
+seed_for_storage!(storages::Tuple, seed=nothing) = 
+    seed_for_storage!.(storages, seed)
 
 
 ### parallel utility function