Merge branch 'signal_tunnels_bridges' into jgrpp

# Conflicts:
#	src/pbs.cpp
#	src/saveload/extended_ver_sl.cpp
#	src/settings_gui.cpp
#	src/settings_type.h
#	src/signal.cpp
#	src/table/settings.ini
#	src/train_cmd.cpp
#	src/tunnelbridge.h

docs/landscape.html

@@ -1607,12 +1607,18 @@
         <td><tt>2</tt>&nbsp;</td>
         <td>signal simulation exit (bit 6 set)</td>
        </tr>
+
+       <tr>
+        <td><tt>3</tt>&nbsp;</td>
+        <td>signal simulation bidirectional entrance and exit (bits 5 and 6 set)</td>
+       </tr>
       </table>
       If signal simulation entrance or exit:
       <ul>
+       <li>m6 bit 7: set = exit signal shows green, clear = exit signal shows red</li>
        <li>m6 bit 6: set = PBS signals, clear = block signals</li>
        <li>m6 bit 1: set = semaphore signals, clear = light signals</li>
-       <li>m6 bit 0: set = signal shows green, clear = signal shows red</li>
+       <li>m6 bit 0: set = entrance signal shows green, clear = entrance signal shows red</li>
        <li>m2 bit 15: for bridge entrances only: storage for visual red/green state of signals starting from 15 is allocated outside the map array</li>
        <li>m2 bits 14..0: for bridge entrances only: for signals 0..14 on bridge, signal is visually red if corresponding bit in 0..14 is set</li>
       </ul>