split wave_variance into two functions:
split wave_variance into two functions:

wave_variance() : gives the wavelet variance

ci_wave_variance() : gives the wavelet variance + 95% CI

Rewrote wvar to take care of it.

Modified bootstrapper.


Former-commit-id: a944e295e889b982c2182b8464be8cead1eaddae
SMAC-Group/gmwm,SMAC-Group/gmwm,SMAC-Group/gmwm,SMAC-Group/gmwm