Remove unnecessary checks for projections
Remove unnecessary checks for projections

This makes projection handling identical to _lcmv.py, simplifies the code, but
adds two unnecessary multiplications by an identity matrix in the (unlikely?)
case of no projections being present.

To justify why the checks are unnecessary:

* the 'projs' key is always expected to be in info
* if there are no projections, the info['projs'] is just an empty list
* if make_projector is passed an empty list, it just creates an identity array

larsoner/mne-python,aestrivex/mne-python,jniediek/mne-python,wmvanvliet/mne-python,jmontoyam/mne-python,adykstra/mne-python,matthew-tucker/mne-python,agramfort/mne-python,trachelr/mne-python,Teekuningas/mne-python,trachelr/mne-python,pravsripad/mne-python,Teekuningas/mne-python,bloyl/mne-python,agramfort/mne-python,pravsripad/mne-python,olafhauk/mne-python,kingjr/mne-python,lorenzo-desantis/mne-python,jaeilepp/mne-python,cmoutard/mne-python,cjayb/mne-python,jniediek/mne-python,kingjr/mne-python,Eric89GXL/mne-python,alexandrebarachant/mne-python,kambysese/mne-python,leggitta/mne-python,Odingod/mne-python,drammock/mne-python,leggitta/mne-python,yousrabk/mne-python,mne-tools/mne-python,drammock/mne-python,alexandrebarachant/mne-python,nicproulx/mne-python,dgwakeman/mne-python,mne-tools/mne-python,effigies/mne-python,andyh616/mne-python,wmvanvliet/mne-python,rkmaddox/mne-python,matthew-tucker/mne-python,teonlamont/mne-python,Odingod/mne-python,effigies/mne-python,drammock/mne-python,mne-tools/mne-python,olafhauk/mne-python,dimkal/mne-python,dgwakeman/mne-python,antiface/mne-python,lorenzo-desantis/mne-python,dimkal/mne-python,teonlamont/mne-python,ARudiuk/mne-python,jmontoyam/mne-python,jaeilepp/mne-python,andyh616/mne-python,ARudiuk/mne-python,wmvanvliet/mne-python,adykstra/mne-python,wronk/mne-python,Eric89GXL/mne-python,bloyl/mne-python,larsoner/mne-python,rkmaddox/mne-python,yousrabk/mne-python,wronk/mne-python,Teekuningas/mne-python,nicproulx/mne-python,larsoner/mne-python,pravsripad/mne-python,olafhauk/mne-python,aestrivex/mne-python,cjayb/mne-python,kingjr/mne-python,kambysese/mne-python,antiface/mne-python,cmoutard/mne-python