A bugfix to prevent macros from being expanded when they are
found as comments inside of other macros. The basis
library TokenReplacer class does not have support for excludes
(I have a dim recollection of a utility that supported excludes)
but even if it did support excludes they would need to be context
sensitive for this purpose. Context-sensitive excludes are not
worth the effort at this time. Any macros detected inside a
comment are converted from %{foobar}% into %_{foobar_}% thus
preventing the macro from being expanded.