Allow specifying upstream egg list uri

Add license file

Update source url

Don't error on files without extension

When checking for egg file. Thanks to Pietro Cerutti for pointing this
out.

Fix typo in docs

Use HTTPS

Add documentation

Add repo to release-info

Add note about chicken-install options

Use optimism, pass other options to chicken-install

Ensure not to downgrade eggs

Add release-info file

Add gitignore, fix deps

Initial release