trigsimp modifications

- In TR11 make sure that a Rational is being handled (i.e. avoid the number oo which does not
have a p or q attribute). This is something that
should be done SymPy-wide: whereever as_coeff_Mul
is being used with the use of .p or .q afterwords
on the extracted coefficient, use the rational=True
argument to as_coeff_Mul, e.g.

    c, m = e.as_coeff_Mul()  # use rational=True!
    ...
    if c.q == foo ...

- the use of cse was removed as this can lead to
  incorrect results (not just different results)
  e.g.

    eq=x*(n-1)-x*n
    trigsimp(eq, recursive=True) -> -x

- sympification is now used

- bottom_up was made a little more flexible in how
  it handles arguments

- futrig sympifies, too

- TR6 has to be used after TR11 in order to keep any
  introduced powers in terms of sin -- a test was
  added that will fail if this is removed.
use bottom_up for futrig