Enhance 'kernel_upgrade' across supported OSes

kernel_upgrade currently searches for the driver
"/lib/modules/${::kernelrelease}/kernel/drivers/scsi/vmw_pvscsi.ko",
which isn't reliable on RHEL/CentOS 5. I've added some conditional
logic to search for vmxnet3.ko instead, which appears to be
universally installed regardless of distro (albeit in different
locations across the different versions of RHEL/CentOS).
Merge pull request #14 from mckern/search_for_vmxnet_driver

Enhance 'kernel_upgrade' across supported OSes
Fixing top-scope variable
Moving config creates to params
Correcting syntax for params
Adding bundler to travis
Updating travis.yaml
Updaing travis.yaml
Fixing travis.yaml
Starting doc update to 0.1.2
Changing curl to present
Changing curl to present
Changing curl to present
Changing curl to present
Changing curl to present
Temporarily disabling archive_url check
Enabling archive_url check
Applying changes referenced in #14
Readme for 0.1.3
Oops - should have been 0.1.2