ENH: return stc when applying stc.transform_data
STY
ENH: add transform method to SourceEstimate class
WIP: add transform method to SourceEstimate class
WIP: add transform method to SourceEstimate class
WIP: add transform method to SourceEstimate class
FIX read_fiducials():  set points' coord_frame
WIP: test SourceEstimate transform method
FIX fiducials IO TEST
ENH write_fiducials:  catch fiducials with inconsistent coord_frame entries
WIP: test SourceEstimate transform method
WIP: test SourceEstimate transform method
FIX: CSP fit bug fixed!
pep8 fixed
Merge pull request #857 from trachelr/csp-fix

FIX: CSP fit bug fixed!
Merge pull request #842 from adykstra/return_stc_data_transform

ENH:  add transform method to SourceEstimate class
Merge pull request #856 from christianmbrodbeck/fid_io

FIX read_fiducials():  set points' coord_frame
ENH:  make spacing parameter consistent between functions
DOC
DOC