Channel naming 100022

Allow editing of channel names.

To test:
 - Choose image in Dataset / Plate / Plate-Acquisition / Orphaned (test all)
 - Click edit button beside channel names in 'General' right panel
 - Edit names and Save (check saved)
 - Edit names and 'Apply to All' (if allowed), check confirm message, click "OK"?
     - Check all images in Dataset / Plate have channels renamed.
     - (won't be renamed if Channel-count is less than the edited image).