typo fixed
A semantics of BVL in terms of a conventional inductive relation.

I tried proving the bInline function correct w.r.t. this more
conventional relational semantics. I quickly realised that
the relation semantics introduces a lot of existential
quantifiers that seem to force proofs to be rather manual.
From now on I'll stick to functional versions of big-semantics
so that rewriting can be used in the correctness proofs.

I'm committing this relation semantics just as a record of this
exercise. However, this relational semantics might not be
maintained in the future.
BVP sem defined, BVL --> BVP defined
stack added to BVP
replace Continue by NONE
replaced Hol_datatype with Datatype
BVL/BVP now use sptrees instead of finite maps
BVP now supports tail-calls
BVL-->BVP correctness thm sketched
make bvlScript.sml non-executable

don't know why it was
BVL-->BVP correctness cases Var and Let
BVL-->BVP Tick case
BVL-->BVP If case
BVL-->BVP Call case proved
wip: Raise case for BVL-->BVP
BVL-->BVP cases Raise and Handle proved
BVL-->BVP last case (Op) proved
BVP-->BVP simple opt for Raise, Return, Skip with Seq and If
BVL-->BVP compiler now adds live var annotations
simplified BVP If-statements