automate new-release ingest

[ab9rf]

about 95% of the process of generating symbols.xml for a new DF release is currently being handled with scan_vtable.rb and dumpdf_globals.rb

the remaining 5% should also be automated if possible

automatically extracting the PE header timestamp should be easy

automatically identifying the locations of steam_mod_manager and game_extra may prove more difficult but we may be able to roll back the whole gamest split after 50.08 rendering this point moot

and assembling the collected bits into a symbols.xml stanza is obviously trivial

[lethosor]

We may be able to reuse https://github.com/BenLubar/dfhack-raft/blob/buildmaster/projects/Dwarf%20Fortress/scripts/dfhack-structures-update.sh for this