Currently when apps like gnome-session call esd and esd is not set to
autospawn, esd does not read esd.conf ESD_SPAWN_OPTIONS or ~/.esd.conf. 
Since esd is often by default not set to autospawn, esd may not work with
certain soundcards that need to specify a rate for esd to work at all (eg
i810_audio needs '-r 48000' to work with esd).

The proposed patch allows esd to work in a more standard way-- it will read
 environment variables (ESD_SPAWN_OPTIONS) and config files (esd.conf and
~/.esd.conf) in addition to parsing command line arguments.

The basic idea of the patch is to take some stuff out of esd_config.c
and put it into a new esd-config.h, so that esd.c can use it, then
modify esd.c (main()) to put esd_spawn_options (as read from esd.conf and
friends) into *opts[], and then put argv after esd_spawn_options in
*opts[]. Then rather than looping through argv, the loop parses *opts[]. 
argv is after esd_spawn_options in *opts[] so that command line arguments
take precedence over esd.conf.

I use esd_config_read() in main() so that esd.conf, ~/.esd.conf and
ESD_SPAWN_OPTIONS are all considered.

The maximum number of combined arguments (argv + esd_spawn_options) is
MAX_ARGS, which in the patch is 128.  This is probably too high, but as
the patch is now, arguments from esd_spawn_options and argv are read
into *opts[], and stops at MAX_ARGS-- any more args are simply dropped. 
So I left it high.

The proposed patch applies cleanly to 0.2.29 and was checked under memprof
with no leaks.