Root nodeid

Change mount type from fuse.mergerfs to mergerfs in README

Add NFS options to remote filesystems section of readme

Add export-support option as possible workaround for NFS EIO issues

Library updates

* Update README.md

Information added that mergerfs v2.35.0 and newer sets `allow_other` (but ...

Fix user.mergerfs.pid

Set flush-on-close default to opened-for-write

Only set allow_other when running as root

Add flushonclose feature

Warn if not running as root

Update wyhash to 4.2

Remove use of pthread_getname_np to work with older musl versions

Rework thread pool queue depth impl

Fix readdir doc typos

Fix thread pool destruction where threads don't explicitly exit themselves

Add some new questions to FAQ

Remove unneeded debug logging from thread pool

Add website and license to version option

Rework thread pool, add ability to add/remove threads at runtime

Add proper input validation for readdir policy

Change threadpool to use concurrentqueue

Initialize readdir threadpool after daemonizing

Docs: clarify parallel-direct-writes and cache.files

Change which 'comm' name -> whose 'comm' name.
Whose implies possession, and the process possess...

This makes it clear, along with the previous commit, that per-process will allow
us to use paral...

Clarify that paralell direct can only be enabled where the kernel
version supports it, which is ...

Misc fixes for older platforms

Use relaxed memory order for atomic counters

Update wyhash to final4

Fix setting of ugids for concurrent readdir

Add thread names for easier debugging

Add ability to invalidate gid cache on demand

SIGUSR2 or ioctl

Fix a typo in README.md

Add callbacks for newer functions

* setupmapping
* removemapping
* syncfs
* tmpfile

Add readdir policies

Fix logging pin-threads details

Move fuse thread args out of fuse session object

Lib updates

Mostly to remind myself which libs to update on occasion

Create functions can set branches RO on EROFS

Align msg buffer memory to allow O_DIRECT to work

Simplify syslog wrapper a bit

Fix build on older distros due to std::atomic definitions

std::atomic_uint64_t missing in some older distros

Fix error handling for cached writes

Add manual GC triggering + configurable process queue depth

Yes, these are unrelated changes but somehow ended up being
prototyped together and I'm too lazy...

Fix move when in append mode + fix read/write direct_io vs cached behavior

Also add parallel direct write option for 6.2+ kernels.

Make srcmounts readonly

All tools only read from srcmounts and the current setup had a bug
which caused branch mode and ...