Merge branch 'maint'

* maint:
  Update draft release notes to 1.6.2.2
  Fix bash completion in path with spaces
  bash completion: only show 'log --merge' if merging
  git-tag(1): add hint about commit messages
  Documentation: update graph api example.

diff --cc contrib/completion/git-completion.bash
index 1c6b0e28eff43caea4d7078d18d196c6d36fbbd4,8431837f9705d9a940819db4fcd51283f433ba1a..e72ce2428dd44176484ed88823dee6dd8707400c
--- 1/contrib/completion/git-completion.bash
--- 2/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@@ -1941,9 -1841,9 +1941,9 @@@ _gitk (
        __git_has_doubledash && return
  
        local cur="${COMP_WORDS[COMP_CWORD]}"
 -      local g="$(git rev-parse --git-dir 2>/dev/null)"
 +      local g="$(__gitdir)"
        local merge=""
-       if [ -f $g/MERGE_HEAD ]; then
+       if [ -f "$g/MERGE_HEAD" ]; then
                merge="--merge"
        fi
        case "$cur" in