Add staff comments to BLSample

I would like to add a staff comments column to BLSample for mail-in mode so staff can relay information on samples to users. This is for the case where a datacollection may not have been created and thus datacollectioncomments cannot be used.

```
ALTER TABLE `BLSample`
	ADD `staffComments` VARCHAR(255) NULL DEFAULT NULL COMMENT 'Any staff comments on the sample', 
```