[Maxima] Translated code and simplification of %pi in presence of numer=true

[Richard Fateman]

If you use numerical approximations in assume,  then you are inserting 
potentially false assertions into Maxima.
e.g.
assume(x>=%pi),numer


is  (x   >= %pi + 10^(-20))   might return true even if it is not 
necessarily true mathematically.

If you want to have a database of assertions which are sometimes true, 
but not always, maybe numerical
evaluation is OK.  Maybe if the assertions already have floating point 
numbers it might be OK.
However, %pi is not a floating point number. 

RJF