templates: rename "user" to "luser" defined in default map file (API)

"user" will be shadowed by the {user} keyword to be added by the next
patch.

I think the naming of template fields is a sort of an internal API, so
this patch is flagged as an API change.

.. api::

   Rewrite ``{user}`` to ``{luser}`` in log templates inherited from
   map-cmdline.default.

mercurial/templates/map-cmdline.bisect

@@ -1,10 +1,10 b''
 %include map-cmdline.default
 
 [templates]
-changeset = '{cset}{lbisect}{branches}{bookmarks}{tags}{parents}{user}{ldate}{summary}\n'
+changeset = '{cset}{lbisect}{branches}{bookmarks}{tags}{parents}{luser}{ldate}{summary}\n'
 changeset_quiet = '{lshortbisect} {rev}:{node|short}\n'
-changeset_verbose = '{cset}{lbisect}{branches}{bookmarks}{tags}{parents}{user}{ldate}{lfiles}{lfile_copies_switch}{description}\n'
-changeset_debug = '{fullcset}{lbisect}{branches}{bookmarks}{tags}{lphase}{parents}{manifest}{user}{ldate}{lfile_mods}{lfile_adds}{lfile_dels}{lfile_copies_switch}{extras}{description}\n'
+changeset_verbose = '{cset}{lbisect}{branches}{bookmarks}{tags}{parents}{luser}{ldate}{lfiles}{lfile_copies_switch}{description}\n'
+changeset_debug = '{fullcset}{lbisect}{branches}{bookmarks}{tags}{lphase}{parents}{manifest}{luser}{ldate}{lfile_mods}{lfile_adds}{lfile_dels}{lfile_copies_switch}{extras}{description}\n'
 
 # We take the zeroth word in order to omit "(implicit)" in the label
 bisectlabel = ' bisect.{word('0', bisect)}'

mercurial/templates/map-cmdline.default

@@ -2,10 +2,10 b''
 # to replace some keywords with 'lkeyword', for 'labelled keyword'
 
 [templates]
-changeset = '{cset}{branches}{bookmarks}{tags}{parents}{user}{ldate}{ltroubles}{lobsfate}{summary}\n'
+changeset = '{cset}{branches}{bookmarks}{tags}{parents}{luser}{ldate}{ltroubles}{lobsfate}{summary}\n'
 changeset_quiet = '{lnode}'
-changeset_verbose = '{cset}{branches}{bookmarks}{tags}{parents}{user}{ldate}{ltroubles}{lobsfate}{lfiles}{lfile_copies_switch}{description}\n'
-changeset_debug = '{fullcset}{branches}{bookmarks}{tags}{lphase}{parents}{manifest}{user}{ldate}{ltroubles}{lobsfate}{lfile_mods}{lfile_adds}{lfile_dels}{lfile_copies_switch}{extras}{description}\n'
+changeset_verbose = '{cset}{branches}{bookmarks}{tags}{parents}{luser}{ldate}{ltroubles}{lobsfate}{lfiles}{lfile_copies_switch}{description}\n'
+changeset_debug = '{fullcset}{branches}{bookmarks}{tags}{lphase}{parents}{manifest}{luser}{ldate}{ltroubles}{lobsfate}{lfile_mods}{lfile_adds}{lfile_dels}{lfile_copies_switch}{extras}{description}\n'
 
 # File templates
 lfiles = '{if(files,
@@ -54,8 +54,8 b' tag = \'{label("log.tag",'
 bookmark = '{label("log.bookmark",
                    "bookmark:    {bookmark}")}\n'
 
-user = '{label("log.user",
-               "user:        {author}")}\n'
+luser = '{label("log.user",
+                "user:        {author}")}\n'
 
 summary = '{if(desc|strip, "{label('log.summary',
                                    'summary:     {desc|firstline}')}\n")}'

mercurial/templates/map-cmdline.phases

@@ -1,5 +1,5 b''
 %include map-cmdline.default
 
 [templates]
-changeset = '{cset}{branches}{bookmarks}{tags}{lphase}{parents}{user}{ldate}{summary}\n'
-changeset_verbose = '{cset}{branches}{bookmarks}{tags}{lphase}{parents}{user}{ldate}{lfiles}{lfile_copies_switch}{description}\n'
+changeset = '{cset}{branches}{bookmarks}{tags}{lphase}{parents}{luser}{ldate}{summary}\n'
+changeset_verbose = '{cset}{branches}{bookmarks}{tags}{lphase}{parents}{luser}{ldate}{lfiles}{lfile_copies_switch}{description}\n'

mercurial/templates/map-cmdline.status

@@ -2,9 +2,9 b''
 
 [templates]
 # Override base templates
-changeset = '{cset}{branches}{bookmarks}{tags}{parents}{user}{ldate}{summary}{lfiles}\n'
-changeset_verbose = '{cset}{branches}{bookmarks}{tags}{parents}{user}{ldate}{description}{lfiles}\n'
-changeset_debug = '{fullcset}{branches}{bookmarks}{tags}{lphase}{parents}{manifest}{user}{ldate}{extras}{description}{lfiles}\n'
+changeset = '{cset}{branches}{bookmarks}{tags}{parents}{luser}{ldate}{summary}{lfiles}\n'
+changeset_verbose = '{cset}{branches}{bookmarks}{tags}{parents}{luser}{ldate}{description}{lfiles}\n'
+changeset_debug = '{fullcset}{branches}{bookmarks}{tags}{lphase}{parents}{manifest}{luser}{ldate}{extras}{description}{lfiles}\n'
 
 # Override the file templates
 lfiles = '{if(files,