chore: add a vagrant config to spin multiple vms

QoL for development. Easily spin multiple vms to run network scans
locally.

My personal cheat sheet for vagrant:
```
\# spin all vms
vagrant up
\# get the ips
vagrant ssh-config | grep HostName | awk '{print $2}'
\# tear everything down
vagrant destroy -f
```

.gitignore

@@ -128,3 +128,6 @@ quipucords/roles/
 
 # local files
 var/
+
+# vagrant data
+.vagrant/

Vagrantfile

@@ -0,0 +1,21 @@
+Vagrant.configure("2") do |config|
+  # unnoficial RHEL images
+  (6..9).each do |n|
+    config.vm.define "rhel%d" % n do |vmconfig|
+      vmconfig.vm.box = "generic/rhel%d" % n
+    end
+  end
+  # unnoficial centos stream images (for testing purposes we can consider them RHEL-like)
+  (8..9).each do |n|
+    config.vm.define "stream%d" % n do |vmconfig|
+      # we could use the official "centos/stream%d" images, but I'm unable to boot stream9 :'(
+      vmconfig.vm.box = "generic/centos%ds" % n
+    end
+  end
+  # allow ssh'ing with password authentication (username and password is "vagrant")
+  config.vm.provision "shell", inline: <<-EOF
+    sed -i 's/PasswordAuthentication no/PasswordAuthentication yes/g' /etc/ssh/sshd_config
+    # fallback to service for systems that don't use systemd
+    systemctl restart sshd.service || service sshd restart
+  EOF
+end