Replace heapster for metrics-server as cluster default.
This requires the following labels as default:
tiller_enabled=true
heapster_enabled=false
metrics_server_enabled=true
depends-on: Idc315937a82317b76349bbe8466d900d00194953
depends-on: Icd7f380d87672c00257e34df385d81e1c3e36ddf
Story: 2004816
Task: 28979
Change-Id: I52970244c8977dc5d1a67e7ad7329897b496a0cb
Signed-off-by: Diogo Guerra <dy090.guerra@gmail.com>