Enable gateway featrue and sync ks-core chart

Created by: RolandMa1986

Signed-off-by: Roland.Ma rolandma@kubesphere.io

What type of PR is this?

/kind feature

What this PR does / why we need it:

This PR adds gateway configuration to the kubesphere-config.yaml config file and enables the feature by default.

Which issue(s) this PR fixes:

Fixes kubesphere#3055 (closed)

/cc @kubesphere/sig-installation