Added support for Amazon linux

Added support for Amazon linux version 3 with Facter 1.7.x.

```bash
# facter | grep -i -e ^o -e ^fac
facterversion => 1.7.1
operatingsystem => Amazon
operatingsystemmajrelease => 3
operatingsystemrelease => 3.4.43-43.43.amzn1.x86_64
osfamily => RedHat
```

Ref:  http://projects.puppetlabs.com/issues/15792

Also updated .gitignore to prevent my IDE messing up the source tree.

Cheers

-Martin