VKEYBD: Add small keyboard pack for virtual keyboard.

This pack contains just the 320x240 layout.

This is a quick way to achieve the result of a smaller keyboard
when running on 640x480 and larger games as requested bu a user.

To use this, the pack zip file, vkeybd_small.zip should be placed
in the extrapath in the same way as vkeybd_default.zip.

However, it is also necessary to set this as the active virtual
keyboard layout by adding the following linein the global [scummvm]
section of the configuration file i.e. scummvm.ini:
vkeybd_pack_name=vkeybd_small

This should be added to the GUI as a misc option, in future.

Currently, the closest layout size to the overlay size is chosen
automatically by the code in the method:
bool VirtualKeyboardParser::parserCallback_mode(ParserNode *node)

This should probably also be made configurable in future to allow
smaller keyboard sizes to be chosen.
README: Add trigger hotkeys for virtual keyboard and keymapper.
VKEYBD: Switch hotkey from F7 to CTRL-F7 to reduce game conflicts.

Although this is harder for physically disabled users to trigger, they
can now use the long middle mouse button press instead to trigger.
KEYMAPPER: Change hotkey from F8 to CTRL-F8 to reduce game conflicts.
FULLPIPE: Proper implementation of FullpipeEngine::stopAllSoundInstances()
MADS: Implement scene 357
MADS: Implement scene 358
FULLPIPE: Implement StaticANIObject::calcStepLen()
FULLPIPE: Implement ModalSaveGame::ModalSaveGame()
FULLPIPE: Implement ModalSaveGame destructor
FULLPIPE: Implement ModalSaveGame::getSaveName()
FULLPIPE: More code to ModalSaveGame
MADS: Implement scene 359
MADS: Implement scene 360
MADS: Show the current scene when using "scene" without params
MADS: Add detection entries for Dragonsphere and Phantom

Also, disable the unsupported compressed Rex version for now
MADS: Set Rex to start from scene 101, like the original

There's a temporary hack to skip showing Rex's standing up animation
cause it takes ages to finish
MADS: Add skeleton classes for Phantom and Dragonsphere
MADS: Add initial support for V2 backgrounds and hotspots

V2 games include Phantom and Dragonsphere. OUAF hasn't been tested yet
MADS: Handle the missing sections in Phantom and Dragonsphere