Removed feature gates selfhosting, HA and store certs in secrets.

Added new alpha command to pivot to self hosted
Removed slelfhosting upgrade ability
Added warning message to self hosted pivot
added certs in secrets flag to new selfhosting comand

docs/.generated_docs

@@ -35,10 +35,10 @@ docs/admin/kubeadm_alpha_phase_bootstrap-token_node.md
 docs/admin/kubeadm_alpha_phase_bootstrap-token_node_allow-auto-approve.md
 docs/admin/kubeadm_alpha_phase_bootstrap-token_node_allow-post-csrs.md
 docs/admin/kubeadm_alpha_phase_mark-master.md
-docs/admin/kubeadm_alpha_phase_selfhosting.md
-docs/admin/kubeadm_alpha_phase_selfhosting_convert-from-staticpods.md
 docs/admin/kubeadm_alpha_preflight.md
 docs/admin/kubeadm_alpha_preflight_node.md
+docs/admin/kubeadm_alpha_selfhosting.md
+docs/admin/kubeadm_alpha_selfhosting_pivot.md
 docs/admin/kubeadm_completion.md
 docs/admin/kubeadm_config.md
 docs/admin/kubeadm_config_images.md
@@ -131,11 +131,11 @@ docs/man/man1/kubeadm-alpha-phase-bootstrap-token-node-allow-post-csrs.1
 docs/man/man1/kubeadm-alpha-phase-bootstrap-token-node.1
 docs/man/man1/kubeadm-alpha-phase-bootstrap-token.1
 docs/man/man1/kubeadm-alpha-phase-mark-master.1
-docs/man/man1/kubeadm-alpha-phase-selfhosting-convert-from-staticpods.1
-docs/man/man1/kubeadm-alpha-phase-selfhosting.1
 docs/man/man1/kubeadm-alpha-phase.1
 docs/man/man1/kubeadm-alpha-preflight-node.1
 docs/man/man1/kubeadm-alpha-preflight.1
+docs/man/man1/kubeadm-alpha-selfhosting-pivot.1
+docs/man/man1/kubeadm-alpha-selfhosting.1
 docs/man/man1/kubeadm-alpha.1
 docs/man/man1/kubeadm-completion.1
 docs/man/man1/kubeadm-config-images-list.1