textscreen: Init screen at native bit depth.

Always call SDL_SetVideoMode with bpp=0 to use the desktop's native
bit depth, and instead draw into an intermediate 8-bit screenbuffer
surface. This ensures that we do not encounter any palette mess-ups
as on some systems true 8-bit screen modes are poorly supported.
hexen: Create HR (startup) screen at native bpp.

Always call SDL_SetVideoMode() with bpp=0 to use the native pixel
depth of the display. This avoids problems with some systems that
don't properly support 8-bit screen modes any more. Draw into an
intermediate buffer and let SDL take care of the pixel depth
conversion for us.
net: Add -nodes command line argument.

This matches the -nodes parameter that ipxsetup has; interpret it as
an "auto-start" parameter that launches the game when the intended
number of clients have joined the server.
video: Change default for screen_bpp to 0.

Some machines don't work well with 8-bit screen depths any more. It's
better to default to just using the machine's native color depth
instead. Change the default to 0 (for SDL_SetVideoMode this means "use
native color depth"), auto-adjust to native color depth on startup if
screen_bpp=0 (so that debug messages at least make sense) and document
for the config file value that a value of zero means "use native".
music: Fix -dumpsubstconfig for Heretic/Hexen.

The config dumping command line option assumed that music lumps were
named like D_MYLUMP, but this is not the case for Heretic and Hexen,
where there is no D_ prefix and music lumps can have any name.

Change the logic to instead look at the contents of lumps and identify
music lumps from the MUS / MIDI header.
setup: Call TXT_Shutdown on exit.

Some systems (fbcon SDL driver) get messed up if not cleanly shut
down. Make sure that we call SDL_QuitSubsystem on shutdown.
Support multi-colored text lines
Revert "Set default conversation algorithm for libsamplerate to Fast Sinc (3), thanks fraggle!"

This reverts commit 3f70b18e82ffae39a5f5ce4bee054e87356e032a.
Merge branch 'master' of https://github.com/chocolate-doom/chocolate-doom

Conflicts:
	src/setup/display.c