wt-status: lift the artificual "at least 20 columns" floor

When we show unmerged paths, we had an artificial 20 columns floor
for the width of labels (e.g. "both deleted:") shown next to the
pathnames.  Depending on the locale, this may result in a label that
is too wide when all the label strings are way shorter than 20
columns, or no-op when a label string is longer than 20 columns.

Just drop the artificial floor.  The screen real estate is better
utilized this way when all the strings are shorter.

Adjust the tests to this change.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t7060-wtstatus.sh

@@ -38,7 +38,7 @@ You have unmerged paths.
 Unmerged paths:
   (use "git add/rm <file>..." as appropriate to mark resolution)
 
-	deleted by us:      foo
+	deleted by us:   foo
 
 no changes added to commit (use "git add" and/or "git commit -a")
 EOF
@@ -142,8 +142,8 @@ You have unmerged paths.
 Unmerged paths:
   (use "git add/rm <file>..." as appropriate to mark resolution)
 
-	both added:         conflict.txt
-	deleted by them:    main.txt
+	both added:      conflict.txt
+	deleted by them: main.txt
 
 no changes added to commit (use "git add" and/or "git commit -a")
 EOF
@@ -175,9 +175,9 @@ You have unmerged paths.
 Unmerged paths:
   (use "git add/rm <file>..." as appropriate to mark resolution)
 
-	both deleted:       main.txt
-	added by them:      sub_master.txt
-	added by us:        sub_second.txt
+	both deleted:    main.txt
+	added by them:   sub_master.txt
+	added by us:     sub_second.txt
 
 no changes added to commit (use "git add" and/or "git commit -a")
 EOF
@@ -203,7 +203,7 @@ Changes to be committed:
 Unmerged paths:
   (use "git rm <file>..." to mark resolution)
 
-	both deleted:       main.txt
+	both deleted:    main.txt
 
 Untracked files not listed (use -u option to show untracked files)
 EOF

t/t7512-status-help.sh

@@ -33,7 +33,7 @@ You have unmerged paths.
 Unmerged paths:
   (use "git add <file>..." to mark resolution)
 
-	both modified:      main.txt
+	both modified:   main.txt
 
 no changes added to commit (use "git add" and/or "git commit -a")
 EOF
@@ -87,7 +87,7 @@ Unmerged paths:
   (use "git reset HEAD <file>..." to unstage)
   (use "git add <file>..." to mark resolution)
 
-	both modified:      main.txt
+	both modified:   main.txt
 
 no changes added to commit (use "git add" and/or "git commit -a")
 EOF
@@ -146,7 +146,7 @@ Unmerged paths:
   (use "git reset HEAD <file>..." to unstage)
   (use "git add <file>..." to mark resolution)
 
-	both modified:      main.txt
+	both modified:   main.txt
 
 no changes added to commit (use "git add" and/or "git commit -a")
 EOF
@@ -602,7 +602,7 @@ rebase in progress; onto $ONTO
 You are currently rebasing branch '\''statushints_disabled'\'' on '\''$ONTO'\''.
 
 Unmerged paths:
-	both modified:      main.txt
+	both modified:   main.txt
 
 no changes added to commit
 EOF
@@ -636,7 +636,7 @@ You are currently cherry-picking commit $TO_CHERRY_PICK.
 Unmerged paths:
   (use "git add <file>..." to mark resolution)
 
-	both modified:      main.txt
+	both modified:   main.txt
 
 no changes added to commit (use "git add" and/or "git commit -a")
 EOF
@@ -707,7 +707,7 @@ Unmerged paths:
   (use "git reset HEAD <file>..." to unstage)
   (use "git add <file>..." to mark resolution)
 
-	both modified:      to-revert.txt
+	both modified:   to-revert.txt
 
 no changes added to commit (use "git add" and/or "git commit -a")
 EOF

wt-status.c

@@ -318,8 +318,6 @@ static void wt_status_print_unmerged_data(struct wt_status *s,
 	if (!padding) {
 		label_width = maxwidth(wt_status_unmerged_status_string, 1, 7);
 		label_width += strlen(" ");
-		if (label_width < 20)
-			label_width = 20;
 		padding = xmallocz(label_width);
 		memset(padding, ' ', label_width);
 	}