Merge branch 'master' into dev

diff --cc gitk
index 5f27c6ac4f8e830f10113e6f99342042a016f2c2,a1eccfc6d278cc013b055256029f5056f81d3b24..4b7b019857b48756e7d07337e26a4da98ab9e56a
--- 1/gitk
--- 2/gitk
+++ b/gitk
@@@ -9678,8 -8791,43 +9843,9 @@@ if {$i >= [llength $argv] && $revtreear
      }
  }
  
 -if {$mergeonly} {
 -    # find the list of unmerged files
 -    set mlist {}
 -    set nr_unmerged 0
 -    if {[catch {
 -      set fd [open "| git ls-files -u" r]
 -    } err]} {
 -      show_error {} . "[mc "Couldn't get list of unmerged files:"] $err"
 -      exit 1
 -    }
 -    while {[gets $fd line] >= 0} {
 -      set i [string first "\t" $line]
 -      if {$i < 0} continue
 -      set fname [string range $line [expr {$i+1}] end]
 -      if {[lsearch -exact $mlist $fname] >= 0} continue
 -      incr nr_unmerged
 -      if {$cmdline_files eq {} || [path_filter $cmdline_files $fname]} {
 -          lappend mlist $fname
 -      }
 -    }
 -    catch {close $fd}
 -    if {$mlist eq {}} {
 -      if {$nr_unmerged == 0} {
 -          show_error {} . [mc "No files selected: --merge specified but\
 -                           no files are unmerged."]
 -      } else {
 -          show_error {} . [mc "No files selected: --merge specified but\
 -                           no unmerged files are within file limit."]
 -      }
 -      exit 1
 -    }
 -    set cmdline_files $mlist
 -}
 -
  set nullid "0000000000000000000000000000000000000000"
  set nullid2 "0000000000000000000000000000000000000001"
+ set nullfile "/dev/null"
  
  set have_tk85 [expr {[package vcompare $tk_version "8.5"] >= 0}]