Making enstaller talk to local server for integration tests

I have added to variables in `config.py`:
 * `webservice_base_url`: which points to https://api.enthought.com
 * `repo_base_url`: which points to http://www.enthought.com/eggs

**Note:** without trailing backslash
You should be able to make it point to your local server.

Do you think we should have something like debug mode ? where we can run `enpkg --debug --rc-file=~/test/.enstaller4rc` ? and move the base URLs to .enstaller4rc, so we don't need to put them in code ?

Also, I have made some minor changes where I felt things were not right at the first look. Looking forward to your reviews and comments.