(svn r1077) Implements scripts/autoexec.scr to get executed on game starting (sign_de)

- %! allows to merge alias parameters
- \% allows to use % in alias strings
- "alias" command now overwrites the old alias list entry

ttd.c

@@ -644,6 +644,8 @@ int ttd_main(int argc, char* argv[])
 
 	// initialize the ingame console
 	IConsoleInit();
+	IConsoleCmdExec("exec scripts/autoexec.scr 0");
+	
 	InitPlayerRandoms();
 
 #ifdef ENABLE_NETWORK