remove unused params/ methods from DataSpecificationGenerator

[Christian-B]

Excluding unittests of the methods

Much of the code is unused.

For example: (this list is NOT complete)

param empty of reserve_memory_region

method declare_uniform_random_distribution

method get_structure_value

method set_structure_value

The real benefit would be if we can strip the corresponding code out of the C side.
Assuming it is actually there!

[rowleya]

I expect not much is implemented on the other side. Note that we pretty much do this all in python / Java as far as I know...

Stripping the DataSpec down to reserve, switch focus, write value, write array would likely cover everything we do. I think we might also do set write pointer and jump, but I wouldn't be surprised if those had been removed at some point (or are about to be in reduce_overhead).