Update to ARM tools.

Triples are now generated with a "mode" variable. This is required to satisfy the "GoodMode" predicate. Before concrete modes were used, e.g. "16" for user mode.

In addition, various performance related enhancements have been made in helperLib (especially with regard to AC rewriting for the "*" operator).
Further updates to the tools linking the L3 ARM model to the decompiler.

A lot of code has been generalised (making it usable with other models) and the performance has been improved.
Updates and improvements to the l3-machine-code decompilation tools.