fix bug 1055268 - Package Socorro

Adds the ability to package an *rpm* of Socorro while not disrupting *tarball* creation.

This can be done in bash by
```bash
$ export BUILD_TYPE=rpm
$ socorro/scripts/build.sh
```

There is also a `make` target for package, but like the install target, it will not work without first exporting environment variables.
@bramwelt yeah this is really what YUM is for :/

I think having it on Jenkins without the version & epoch would be good, ```socorro-latest.x86_64.rpm``` or so, and have Jenkins archive that.