- Added special mode to all plugin entry functions that returns the plugin type.
- The plugins search function now temporarily loads all available plugins and
reads the plugin type using the new mode PLUGIN_PROBE.
- Added "loadtype" to the plugin structure to store the type used for plugin
loading (currently only the voodoo plugin provides two types).
- bx_shadow_bool_c: removed unused bitnum feature and changed data type.
- Changed return type of memory handlers to bool.
- Modified virtual timer, PIC and PIT code.
plugin_entry(). The additional boolean argument "init" is used to select the
requested action. The entry points still have unique names for compatibility
with the "non-plugin" compilation. Added macros for setting up these names
(e.g. PLUGIN_ENTRY_FOR_MODULE for device plugins).
