Add better profiling of heap for --profile-heap

[AbrarQuazi]

--profile-heap currently lacks proper metrics to debug OOM issues and varies from the information provided from valgrind. This PR adds more relevant information about the garbage collector for each GC cycle, while also adding extra information in profiling csv file.

Example generated CSV file:
heap_log.csv

[AbrarQuazi]

Instead of having this entire class, and using an unordered_map to store heap age, I could have simply had a field inside HeapObject that keeps track of age for all HeapObjects:

wake/src/runtime/gc.h

Line 98 in 2fe5d90

struct HeapObject {

However, when I did this I had issues with alignment, as we have a strict requirement of having 8 bytes alignment for all GCObjects:

wake/src/runtime/gc.h

Line 362 in 2fe5d90

static_assert(sizeof(PadObject) == alignof(T), "HeapObject alignment wrong");

and I felt hesitant to change this requirement.