1.5.5_rc3: Revert "Variableize Busybox image"

This reverts commit ccafe0a980c82407ec6fc8d2913a2edff040eed3.

1.5.5_rc2

Use thin provisioning for cloning

vmware tag

http/https proxy support
static hostnames and ip addresses
configurable names for API and cluster names
vsphere extensions for kubernetes