Fix missing operator-sdk dependency goautoneg

Fix missing operator-sdk dependency goautoneg

goautoneg used to be available from bitbucket.org/ww/goautoneg
but not anymore. operator-sdk has been importing it from
github.com/munnerz/goautoneg for some time now but since we were
using operator-sdk v0.9.0, it was still pointing at the old (now
deleted) repository.

This patch bumps operator-sdk to v0.19.0 (which doesn't use
goautoneg from bitbucket), controller-runtime to v0.5.11, helm to
v2.16.12 and all k8s.io dependencies to v0.16.9 (consistent with
the k8s v1.16.9 we use).

Code changes have been made to make all modules compatible with
the new dependencies.

All src go.sums have been cleaned (deleted and re-built).

Issue-ID: MULTICLOUD-1143
Change-Id: I89fc39e9595b4a6a38dd90028b161bcecd3ef349
Signed-off-by: Igor D.C <igor.duarte.cardoso@intel.com>