[LogisticsBundle] Prevent sending search queries when barcode is entered
[LogisticsBundle] Disable form submit on invalid data, DRY up
[LogisticsBundle] Fix prefilling return barcode
[LogisticsBundle] Add comment field to lease & return
[LogisticsBundle] Only show items that are valid in typeaheads
[LogisticsBundle] Only trigger $barcode.change() when barcode is manually entered
[LogisticsBundle] Ensure UI consistency

Remove error messages on focus
Also detach .help-block when .help-inline is detached
Fetch additional info with barcode check
Untangle code a bit, add documentation