Copied and pasted _refresh_cb from omero_image.html to preview
Channel btn onCilck refs OME.preview_viewport not 'viewport'
Adding more js and html from omero_image.html to preview
Channel sliders and buttons mostly working in Preview
Update channel buttons on channelChange
Common viewport code into omero_image.js DRY
Moving applyRDCW() to omero_image.js
Move channelChange() to omero_image.js
Update channel checkboxes when toggling channel btns
Added channel picker to preview panel
Adding link '999' templates to omero_image.html for omero_image.js
Start / end inputs show min / max via tooltips
One row per channel in rdef table
'Save' btn working -> setImageDefaults() in omero_image.js
'Reset' btn working -> resetImageDefaults() in omero_image.js
'Default' btn working -> resetRDCW() in omero_image.js
Show channel buttons to left of viewport
Moving buttons and hiding unwanted ones for now
Update on color change - 'OK' in picker
Apply on slider 'stop' or start/end 'Enter'