Merge branch 'sg/completion-no-column' into maint

The completion script (in contrib/) used to list "git column"
(which is not an end-user facing command) as one of the choices

* sg/completion-no-column:
  completion: remove 'git column' from porcelain commands

diff --cc contrib/completion/git-completion.bash
index 482ca84b451ba7049b702cac7f737ecf4a65fa05,a795410915e6d08133285a19e9cbbc07daafa519..b383ed05c3483d3ac42f404a62505f0fa9e7c2a2
--- 1/contrib/completion/git-completion.bash
--- 2/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@@ -663,10 -663,11 +663,11 @@@ __git_list_porcelain_commands (
                check-mailmap)    : plumbing;;
                check-ref-format) : plumbing;;
                checkout-index)   : plumbing;;
+               column)           : internal helper;;
                commit-tree)      : plumbing;;
                count-objects)    : infrequent;;
 -              credential-cache) : credentials helper;;
 -              credential-store) : credentials helper;;
 +              credential)       : credentials;;
 +              credential-*)     : credentials helper;;
                cvsexportcommit)  : export;;
                cvsimport)        : import;;
                cvsserver)        : daemon;;