Minor errors in README.md

[threepistons]

$ git clone https://github.com/ycd/toc 
$ cd ycd

should say

$ git clone https://github.com/ycd/toc 
$ cd toc

because git clones to a directory called "toc".

Likewise

# May require you to use sudo
$ go build .
$ cp toc /usr/local/toc

should say

$ go build .
# May require you to use sudo
$ cp toc /usr/local/bin

because the go build . step writes to a place that the user can write to, but "/usr/local/bin" is not where a user can usually write to. "/usr/local" isn't in most people's $PATH but "/usr/local/bin" is.