Reworked `SimulatedClassPool >> #associationAt:ifAbsent:` to throw an error
...if there's no such class variable. This makes it behave more like
dictionary / pool.
syntax: glob
*.chg
*~
*.orig
*.o
*.so
*.sc
*Init.c
*.H
*.STH
*/makefile
*/docs/output/*
*/docs/*.xml.profiled
*/objbc
*/objvc
*.res
*-Test.xml
*.base
*.orig
*.local
*.other
makefile