Revert "Use C99"

Nevermind, glib-1.2 is multiply defining these functions:

g_bit_nth_lsf
g_bit_nth_msf
g_bit_storage

It doesn't compile with clang either, regardless of the C99 flag.

This reverts commit 6a6f8f8da74b712c2842e274f9655b556dec13f9.
Move similar declarations to gtuxnes.h
Hide some local functions
Clean up pointer/int conversions
Convert func() to func(void)
Give local functions static linkage
Strip trailing whitespace
Fix space-before-tab errors
Switch to K&R bracketing
Remove unreachable 'break' statements
Constify pointers to static strings
Simplify the tuxnes option array construction

Print the entire list of options at the end instead of incrementally to
eliminate some duplication.  Do the cleanup once, at the end.
Upgrade to GTK+-2.0
Constify more string pointers

According to [1] the argv parameter to execvp is completely constant,
neither the strings nor the array of pointers are modified.  However it
was decided to not encode this in the parameter's type (to avoid casts
in existing correct code), so we have to cast to that type.

[1] http://pubs.opengroup.org/onlinepubs/009604499/functions/exec.html
Convert from GtkSignal to GSignal
Fix various config file reading bugs

If a key=value pair contains a space (such as "SNDFORMAT0=8-bit Signed"
then scanf() stops at the space.  Parsing continues after the space,
which usually fails and the rest of the file is discarded.  Fix this by
reading in entire lines at a time.

If the parser finds 10 characters that looks like a key, it will try to
match it against the known keys.  However if the 10 characters are not
one of the known keys, then it will walk off the end of the array and
segfault.
Move config.[ch] to settings.[ch]
Move dummy.h to config.h
Use PACKAGE_NAME for the window title
Use gtk_widget_show_all() instead of multiple gtk_widget_show()s