Merge branch 'master' of https://github.com/GBeret/mne-cpp
averaging pre-/poststimulus samples
dbg/chn: treebased xml file building
averaging & covariance estimation
Merge branch 'master' of https://github.com/mne-tools/mne-cpp
Merge branch 'master' of https://github.com/LostSign/mne-cpp
CHG: comments, coding standards