#175 OnBC: Improve Optimisation

[Steve Little]

It would be great if OnBC generated did some better
optimisation when generating code. I'm sure this has
been added as a task and voted on before, but I can't
find it now.

Since "improve optimisation" is such an open ended
task, I suggest individual improvements be added as
seperate tasks so they can be better tracked. A link to
each one can be added as a comment on this task.