Upgrade all dependencies

[nyurik]

This also removes tower as unused, and sets MSRV

Note that brotli crate should not include ffi (causes lots of compilation issues, and is not usually needed)

[nyurik]

@hanabu I updated dependencies. Are you still active on this project? Do you need help maintaining it? Thx!

[nyurik]

Hi, a friendly ping if I can help with getting this merged. I tried emailing you at webmaster@hanabusa.net, but it returned with "user not found". Thx :)

[nyurik]

@hanabu 👋

[0kju0]

@nyurik Maybe, you should create a new cargo package and public to cargo.
He did not maintain this project anymore.

[nyurik]

@hanabu would you be interested in adding me or some other people as maintainers of this project? I will be happy to try to keep it up to date.

[nyurik]

@kju196 while we may have to do that, I would much rather continue developing of the existing project because that would not cause a split in the community. There are many projects already using this crate, and they won't even notice that the crate has been forked.