[release-3.1] combine some feature fixes by cherry-pick
Created by: zhu733756
cherry-pick-to-release-3.1
The pr description updates as following:
- commit 1 update kubespheredev image addr to support kubeedge v1.6.1, from #1527 at branch master, which have conflicts with current pr, have added a commit to fix conficts.
- commit 2 support external prometheus stack, fix #1503 (closed) , from #1528 at branch master.
- commit 3 update kubedge offical image addr to support kubeedge v1.6.2. from #1542 at branch master.
/cc @benjaminhuo @pixiake