Fix: Prompt change in newer versions of git; README file

[mrflip]

Recent versions of git cause the program to emit Password for 'https://[email protected]': ' not a simple Password:.

I made it only compare the leading part of the prompt, to re-use the same prompt it was given, and to give slightly more descriptive error messages.

Also added a README.md file (cribbed from your blog post) and a .gitignored ./build directory (to allow project to build in a relative directory.

Thanks for this -- really helpful!

[crishoj]

Please pull this one – the Homebrew guys don't like formula which point to forks