Detect something like .rsvmrc

[Ailrun]

Is there a way to load specific Rust version automatically?
If there is no way to do that, how about adding .rsvmrc and automatically detect it when cd(or popd, pushd, ...) occurs?
As far as I know, version manager like nvm does so.

[d3m3vilurr]

in current version, just work as old style nvm.
so just check & use $RSVM_DIR/current for default binded version.

[acao]

for anyone looking for the conventional approach to this with the current toolchain:
https://stackoverflow.com/a/64701936/1516887