Telling nailing-cargo how to massage `Cargo.toml`
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-To find the subdirectories, and the packages, it looks for `subdirs`
-and `packages` in `Cargo.nail`.
+To find the subdirectories, and the packages, nailing-cargo looks for
+`subdirs` and `packages` in `Cargo.nail`.
For straightforward use, write `subdirs` as a multi-line string
containing a list of subdirectory names one per line. In each of