When selecting an anchor tissue or gene, delete all other displayed panels

[amkwong]

When the user chooses a new anchor tissue or gene, it should do two things:

1. Set the combination of anchor tissue + anchor gene as the current anchor
2. Display the anchor tissue+gene as the anchor panel
3. Delete all other non-anchor panels

We may want to warn the user that we are deleting the other panels.

[abought]

Based on discussion with Alan, I have a proposed plan for doing this, and can pick up this ticket. (or coordinate with Mukai if he is working on it already)

[mkbwang]

I have made a commit that can achieves this functionality. Let me know if I miss anything.

[amkwong]

Thanks for the commit on this, Mukai - it works well.

We can keep this issue open for now as work-in-progress, with the goal of changing how the URL / query terms work in region view to dynamically reflect the current state of the panels as you scroll, add/delete panels, and change anchors.

Or we could close this issue and use #43 for the consolidated fix.

[amkwong]

We want to change the region view so that the URL reflect the anchor tissue and anchor gene. My initial thought would be something along the lines of ?anchortissue=Adipose_Subcutaneous&anchorgene=...

If either is absent, then my database can fill in with suggestions.