Cargo.toml parsing expects path key when [lib] section is found.

[mendelt]

Thank you for making cargo readme available. While using it I found a small issue

I tried running cargo readme on a crate with proc macro's in it. It had this section in its cargo.toml

[lib]
proc-macro = true

This causes cargo readme to fail with the error "Error: missing field path for key lib" First of all this error could be made clearer, where was this field missing? what file? But when the path key is not found it should just use the default src/lib.rs For now I can get around this by adding

path = "src/lib.rs"

to Cargo.toml

[mendelt]

I created a pull request where lib or bin sections without a path will just default to src/main.rs or src/lib.rs. If that's ok with you I can add some tests for it. I also found some deprecated warnings that I fixed. I'll add a separate pull request for those.

[Charles-Johnson]

path = "scr/lib.rs"

Should be path = "src/lib.rs"

[mendelt]

Should be path = "src/lib.rs"

Thanks! I fixed it. I had to read the text 10 times though before I saw where I mistyped :-)