Clarify range limitations for tensors

Catch zero and negative sized tensors.
Clarify configuration of bool_t in the reference model.
int4_t limitations on -8 to stay symmetric around 0.
Pad values must be >= 0.
Stride,dilation values must be >= 1.

Change-Id: Idb6ef740f855912a8340475ba319816f90c9b051
Signed-off-by: Eric Kunze <eric.kunze@arm.com>