Fix bug in mt_mpmc.c, in Linux mutexes are not recursive.
Add arena_trim_string() to the arena API
Removing arena->path, now paths are pushed to arena->metadata
Replacing fe->owner[128] with char *owner; the owner is not pushed as a
string to arena->metadata and trimed with arena_trim_string()
Improving cache locality in arena->metadata, the memory layout is not
fe; fe->path; fe->owner.
Cache aligning all arenas except HasherContext->arena to sizeof(void *).
Pushing elements one by one instead of snprintf() in finalize_file() and
hash_worker().
Getting the full path of current directory instead of "."
Fixing bug in path formating, this allow us to remove normalize_path()
from the hot loop.
The windows implementation is disabled, currently registering files in
IO Ring when there is inflight IO operations causes corruptions.
Implementing a config file.
Some code cleanup
Making the MPMC queue support when producers are consumers at the same
time by adding a variable work, mpmc_push_work() that increments work
and mpmc_task_done() that decrements work, and if work = 0 calls
mpmc_producers_finished() that pushes poinsons to wake up sleeping
threads and make them return NULL
Replacing DirQueue, a queue growable with realloc with the MPMC queue
Instead of writing directly to file_hashes.txt, hash_workers now are
using a local arena, writing everything once at the end
using #pragma once to ensure that a given header file is included only
once in a single compilation unit
