Adds comments for switchable-linear-process

Modifies linear process for sending multiplexed events to
upper levels.
Adds correct matching of labware barcode on source/destination
for bed verification
Bed verification loads robot barcode listening to event name
defined in contextual configuration
Only shows windows of the gel if they have a sample inside.
Download button of gel scoring is right aligned with the box of the
float panel
Reload table when new scoring is added. Style modification
for correct displaying scrollbars.
Fix comments
Merge pull request #381 from emrojo/checking-correct-barcode-gel

Checking correct barcode gel