Issue 1: Allow non-root to run program

Hi iElectric,

I faced exactly isssue https://github.com/iElectric/g-pypi/issues/1. The suggested modifications will allow you to do...

```bash
gpypi create -l pypi --config-file=$HOME/$CONFIGFILE $PACKAGE
```

...as a normal user. A warning will be issued, when you are not in the group that portage runs in when syncing with the main tree.

Cheers,
Dirk.