upgrade fuse to fuser for Mac support

[dev-jwel]

Upgrade to support Mac.
fuse package returns error even osxfuse has installed for Mac.

Package osxfuse was not found in the pkg-config search path.
Perhaps you should add the directory containing `osxfuse.pc'
to the PKG_CONFIG_PATH environment variable
No package 'osxfuse' found
Package osxfuse was not found in the pkg-config search path.
Perhaps you should add the directory containing `osxfuse.pc'
to the PKG_CONFIG_PATH environment variable
No package 'osxfuse' found
', /Users/jwel/.cargo/registry/src/github.com-1ecc6299db9ec823/fuse-0.3.1/build.rs:10:76
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

However, it is works well for fuser which is fork of the fuse.

[gaul]

Could you rebase and push again? I believe I fixed the CI.

[dev-jwel]

I merged it to run CI.

[gaul]

This still needs rebasing and please get rid of the merge commits. I'm not too sure what this is doing so it might make sense to send individual PRs.

[dev-jwel]

#68 follows this. CI will fail if divide the PR as fuse-rs v0.3 use Timespec but fuse-rs v0.4 and fuser does not. I described the change in the commit instead. Feel free to ask me if some change is strange.