Alter World to use Persistence instead of storing data in historical figures.
Fake historical figures will be converted to the new format when a world is loaded.
Added plugin_save and plugin_load functions to the plugin API.
Made the weird int7/int28 code that was in the old persistence API slightly safer.
This is an incompatible change to the plugin ABI.
The Console is not thread-safe unless used indirectly
via color_ostream_proxy, so everything should use their
per-thread stream.
lethosor
Josh Cooper
Ben Lubar
Petr Mrázek
Alexander Gavrilov