Changes to ETM distribution for release 1.07.


In 1.06, function names were actually defined as the name with a trailing
underscore to causes failure at link time as a reminder that etm.h wasn't
included in source files in which it was needed.  The definitions now use
leading underscores.  A user will consider library symbols to be part of
the system name space and not user name space, so this change is more
consistent with that conceptualization.