ENH: add ems filtering

cosmits

revert
BUG: add test + remove typo
cosmits
FIXES
FIX stupid bug
ENH: add test
ENH: more tests + streamline example
FIX: curdir
whats new

cosmit
cosmits + typos ... (thanks mainak)

cosmits ...
cosmits ... more for mainak
cleanup
typos+cosmits
cleanup + adding comments to address
ENH: improve tests
ENH: smarter API + advanced condition handling
FIX/Optimize computation
ENH: multi channel support

ENH: multi channel support cosmits