No need to do a full repack when expanding and collapsing an individual tier.

git-svn-id: https://svn.code.sf.net/p/genoviz/code/trunk@15366 80d5a9c2-7d8c-4c9f-9369-4e03bca4d2bd
The changes are made so that the selection option is not shown when alignment is not there

git-svn-id: https://svn.code.sf.net/p/genoviz/code/trunk@15367 80d5a9c2-7d8c-4c9f-9369-4e03bca4d2bd
The shade based on quality score has been toggled to false which makes the track shade false

git-svn-id: https://svn.code.sf.net/p/genoviz/code/trunk@15368 80d5a9c2-7d8c-4c9f-9369-4e03bca4d2bd
Changing return type to avoid unchecked exception. 

git-svn-id: https://svn.code.sf.net/p/genoviz/code/trunk@15369 80d5a9c2-7d8c-4c9f-9369-4e03bca4d2bd
Merge remote-tracking branch 'upstream'