decomposition and splitting for NEL

Hi Frogs,

In preparation for the exciting developments in quantum causal evolution, 
we revised the old paper "A System of Interaction and Structure IV: The 
Exponentials" on the normalisation theory of NEL.

Encouraged from referees, we split the paper into two parts, one about 
decomposition and the other about splitting. We think that this makes the 
whole matter clearer and more accessible. Please do not cite the old 
paper, the new ones are better.

Comments of any kind are very welcome.

Best regards,
Alessio and Lutz

----------------------------------------

Title: A System of Interaction and Structure IV: The Exponentials and 
Decomposition

L. Strassburger and A. Guglielmi

Abstract:
System NEL is the mixed commutative/non-commutative linear logic BV
augmented with linear logic's exponentials, or, equivalently, it is
MELL augmented with the non-commutative self-dual connective
seq. System NEL is Turing-complete, it is able to directly express
process algebra sequential composition and it faithfully models causal
quantum evolution. In this paper, we show a basic compositionality