The history files in Vic3 are fairly simple. Files under common/history/ have keyword = { effect... } as top-level blocks,
where the effects from the same keywords are all added together. The keywords seem to be arbitrary, except for GLOBAL which
is documented to go last.
The order in which history files are processed by the game engine.
It was determined by adding debug_log entries to the history files.
LAST UPDATED VIC3 VERSION 1.9.7
TODO: order was rearranged in 1.10