factoring reduction code for trig functions
adding two trigonometric constants
bad comment in deginrad
constant 1/90
using the constants in reduce functions
 factorizing double simd/scalar trig reduction
 factorizing float simd/scalar trig reduction
 factorizing float/double trig reductions
 static choice at the clipped level instead of run-time if
coorecting /more_cosine.cpp
in order it doesnot enter an infinite loop (bench)
suppresing commented includes in trigo.hpp
switch in reduction is replaced par successive statically computed recurssive calls
suppressing use of useless 'internal' namespace in trigonometric
suppressing use of useless 'internal' namespace in exponential
last 'statification' of the trig reduction strategies