EQ settings: Rework the settings to clean up the config file.

Instead of 3 cfg lines per eq band there is now a single line
for each:
<config name>: <cutoff/center freq>, <q>, <gain>

In addition, the config value names make a bit more sense.

The old settings are still readable but config.cfg and any new
settings files will be written with the new config values. (The
old settings will be removed completly sometime after the next
stable release).

Also a slight rework of the advanced EQ menu UI

Change-Id: I9008658d36ded442a5f2f825916df42a3934cbef
Reviewed-on: http://gerrit.rockbox.org/394
Reviewed-by: Jonathan Gordon <rockbox@jdgordon.info>

apps/plugins/settings_dumper.c

@@ -37,6 +37,8 @@ static void write_setting(const struct settings_list *setting, int fd, unsigned
                                         F_EQSETTING|
                                         F_SOUNDSETTING)))
         return;
+    else if (setting->flags&F_DEPRECATED)
+        return;
     setting_count++;
     if (setting_count%10 == 0)
         rb->fdprintf(fd, "\r\n");