Add "pointer scan"-like feature on README (C++) about libmem

[rdbo]

Name suggestions:
LM_GetPointerMap
LM_GetDeepPointer
LM_ReadPointerMap
LM_ResolvePointerMap
LM_DerefPointerMap
LM_AccessPointerMap
LM_PointerMap
LM_UnwrapPointer
LM_MapPointer
LM_DeepPointer

[rdbo]

Sketch:

lm_void_t *
LM_DeepPointer(lm_address_t base, lm_address_t *offsets, lm_size_t noffsets);

template <typename T>
T *LM_DeepPointer(lm_address_t base, std::vector<lm_address_t> &offsets);

Usage:

int *player_health = LM_DeepPointer<int>(some_addr, { 0xF0, 0xA0, 0xE0 });

[rdbo]

TODO: Add LM_DeepPointer example on README, it's very attractive to Cheat Engine users