* lib/gdb.exp: Close connection to remote host if gdb doesn't

	* lib/gdb.exp: Close connection to remote host if gdb doesn't
 	initialize.
	(default_gdb_init): New procedure; allow gdb_init to be overridden
 	by a target configuration file.
	(gdb_expect): Pass the timeout to remote_expect.

	* config/dos.exp(dos_wait): Add timeout parameter.

	* lib/remote.exp(remote_expect): Add timeout parameter.
	(remote_wait): Ditto.
	(standard_wait): Ditto. Also give up if the program outputs
	more than 512,000 bytes.

	* config/vxworks.exp: Use timeout parameter instead of setting
	timeout variable.
	* config/dos.exp: Ditto.
	* config/ddb.exp: Ditto.
	* lib/mondfe.exp: Ditto.
	* lib/rlogin.exp: Ditto.
	* lib/telnet.exp: Ditto.
	* config/base68k.exp: Ditto.
	* config/i386-bozo.exp: Ditto.
	* config/gdb-comm.exp: Ditto.
	* config/gdb_stub.exp: Ditto.
	* config/i960.exp: Ditto.
	* config/ddb-ether.exp: Ditto.
	* config/sim.exp: Ditto.

	* lib/g++.exp(g++_init): Use g++_include_flags instead of making
	up the includes ourselves.