FIX brainvision:  ELP point coordinates

 - fix variable name conflict
 - allow complete customization of point order in ELP files
TEST brain vision:  save Raw with buffer size smaller than file
FIX brainvision: event handling

 - only read events once
 - FIX create stim channel when buffer is not whole file
FIX:  remove unused parameter
ENH:  Option to fix psychtoolbox/stimtracker events

Option to fix events from a vmrk file from a recording where triggers were
sent by psychtoolbox and recorded through the stim tracker (KIT setup)
STY
OPT:  make KIT and brainvision readers to share read_elp

(move read_elp to mne.coreg)
TEST:  read_elp