Merge pull request #140 from liminsun/master

Fill the fiff fields with the received gain info and sensitivity coeffic...
stream add
Merge branch 'master' of https://github.com/mne-tools/mne-cpp
removing calibration when storing
Modify the GainInfoUpdate. Add one new command infg to achieve the gain information before starting to save the fiff file. The GainInfoUpdate is also not necessary to call if you did not change the gain after first connection.