Applied astyle on macros.h
Added macro for getting the bitcount of a type
Added macros to create bit LSB/MSB masks
Added macro for computing the power(n, m) of constant values
Added implementation for func that computes bucket index by hash
Fix: the rs_ht_init() function should take the initial bucket cnt
Fix: Naming, do not add the rs_ prefix here, it is all internal
Added function implementation (empty bodies)
Added implementation for ht_init()
Added implementation for ht_destroy()