correct twiddle factors if input and output is shifted at once
Merge branch 'master' of https://github.com/mpip/pfft
Merge branch 'master' of https://github.com/rainwoodman/pfft into rainwoodman-master
do not clear input for inplace transforms
Merge branch 'rainwoodman-master'
do not clear input in stand alone forward FFT test for user manual
update user manual
exclude zero input form timing
remove expanded header file that was created for writting the user manual
add Yu Feng to acknowledgments