gemfile update. npm script to amdify bionode

Signed-off-by: Anurag Priyam <anurag08priyam@gmail.com>
Add empty Browser.selectionRemoved method.

Fixes the issue that "double clicking an exon was no longer selecting the
transcript".

Signed-off-by: Anurag Priyam <anurag08priyam@gmail.com>