Clear out std, not std tools
Clear out std, not std tools

This was a typo that slipped in, and meant that we were still not properly
clearing out std.

aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust