Isaac working

Changes mostly to do with storage of names:

• MuName's are now Arc<String> as opposed to String
• Only names the client gives my gen_sym are stored in id_name_map and name_id_map (so that id_of and name_of will only work with these)
• Bootimages now only use id_name_map and name_id_map when the client calls id_of and name_of
• Only names for whitelisted entities are dumped in the boot image
• Now use a new version of rodal that allows for better debugging output
• Added a test to check that spilling accros swapstacks works properly

The changes to how names are stored and dumped makes boot image building significantly faster. (I am currently testing this on aarch64, it should all work perfectly)