better input message parser
forgotten quotes
make it static
remove from the cache is a new value is being set

if no previous value is present arc_remove() will do nothing
ensure not trying to fetch the same object multiple times

ensure having only the outer thread setting a new value in the cache for a given object
if there are other threads concurring to fetch the object, they will reuse the value fetched
by the first one
debugging messages + minor cleanings
major fixes (it now works as expected !!)
ensure returning undef if the chunk is empty