[Bug] FileLock dependency incompatible with filesystem
Environment is Ubuntu 18.04, Python 3.7.5, nlp==0.3.0, filelock=3.0.12.

The external volume is Amazon FSx for Lustre, and it by default creates files with limited permissions. My working theory is that FileLock creates a lockfile that isn't writable, and thus there's no way to acquire it by removing the .lock file. But Python is able to create new files and write to them outside of the FileLock package.

When I attempt to use FileLock within a Docker container by writing to `/root/.cache/hello.txt`, it succeeds. So there's some permissions issue. But it's not a Docker configuration issue; I've replicated it without Docker.
```bash
echo "hello world" >> hello.txt
ls -l

-rw-rw-r-- 1 ubuntu ubuntu 10 Jun 30 19:52 hello.txt
```
I'm downloading a dataset successfully with
`load_dataset("wikitext", "wikitext-2-raw-v1")`

But when I attempt to cache it on an external volume, it hangs indefinitely:
`load_dataset("wikitext", "wikitext-2-raw-v1", cache_dir="/fsx") # /fsx is an external volume mount`

The filesystem when hanging looks like this:
```bash
/fsx
----downloads
       ----94be...73.lock
----wikitext
       ----wikitext-2-raw
             ----wikitext-2-raw-1.0.0.incomplete
```

It appears that on this filesystem, the FileLock object is forever stuck in its "acquire" stage. I have verified that the issue lies specifically with the `filelock` dependency:
```python
open("/fsx/hello.txt").write("hello") # succeeds

from filelock import FileLock
with FileLock("/fsx/hello.lock"):
    open("/fsx/hello.txt").write("hello") # hangs indefinitely
```

Has anyone else run into this issue? I'd raise it directly on the FileLock repo, but that project appears abandoned with the last update over a year ago. Or if there's a solution that would remove the FileLock dependency from the project, I would appreciate that.
[Bug] FileLock dependency incompatible with filesystem 
 I'm downloading a dataset successfully with
`load_dataset("wikitext", "wikitext-2-raw-v1")`

But when I attempt to cache it on an external volume, it hangs indefinitely:
`load_dataset("wikitext", "wikitext-2-raw-v1", cache_dir="/fsx") # /fsx is an external volume mount`

The filesystem when hanging looks like this:
```bash
/fsx
----downloads
       ----94be...73.lock
----wikitext
       ----wikitext-2-raw
             ----wikitext-2-raw-1.0.0.incomplete
```

It appears that on this filesystem, the FileLock object is forever stuck in its "acquire" stage. I have verified that the issue lies specifically with the `filelock` dependency:
```python
open("/fsx/hello.txt").write("hello") # succeeds

from filelock import FileLock
with FileLock("/fsx/hello.lock"):
    open("/fsx/hello.txt").write("hello") # hangs indefinitely
```

Has anyone else run into this issue? I'd raise it directly on the FileLock repo, but that project appears abandoned with the last update over a year ago. Or if there's a solution that would remove the FileLock dependency from the project, I would appreciate that. 
 Environment is Ubuntu 18.04, Python 3.7.5, nlp==0.3.0, filelock=3.0.12.

The external volume is Amazon FSx for Lustre, and it by default creates files with limited permissions. My working theory is that FileLock creates a lockfile that isn't writable, and thus there's no way to acquire it by removing the .lock file. But Python is able to create new files and write to them outside of the FileLock package.

When I attempt to use FileLock within a Docker container by writing to `/root/.cache/hello.txt`, it succeeds. So there's some permissions issue. But it's not a Docker configuration issue; I've replicated it without Docker.
```bash
echo "hello world" >> hello.txt
ls -l

-rw-rw-r-- 1 ubuntu ubuntu 10 Jun 30 19:52 hello.txt
```