main: A slightly more compact presentation of the main help text

This just reduces the amount of space between different elements on in the
main help output from four columns to two. The main motivation here was
to give some of the longer command descriptions a little more horizontal
breathing room, but subjectively I also find the tighter column gutters
easier to scan. Others may disagree, of course.

help.go

@@ -55,11 +55,10 @@ Main commands:
 All other commands:
 %s
 Global options (use these before the subcommand, if any):
-    -chdir=DIR      Switch to a different working directory before executing
-                    the given subcommand.
-    -help           Show this help output, or the help for a specified
-                    subcommand.
-    -version        An alias for the "version" subcommand.
+  -chdir=DIR    Switch to a different working directory before executing the
+                given subcommand.
+  -help         Show this help output, or the help for a specified subcommand.
+  -version      An alias for the "version" subcommand.
 `, listCommands(commands, PrimaryCommands, maxKeyLen), listCommands(commands, otherCommands, maxKeyLen))
 
 	return strings.TrimSpace(helpText)
@@ -88,7 +87,7 @@ func listCommands(allCommands map[string]cli.CommandFactory, order []string, max
 		}
 
 		key = fmt.Sprintf("%s%s", key, strings.Repeat(" ", maxKeyLen-len(key)))
-		buf.WriteString(fmt.Sprintf("    %s    %s\n", key, command.Synopsis()))
+		buf.WriteString(fmt.Sprintf("  %s  %s\n", key, command.Synopsis()))
 	}
 
 	return buf.String()