Improvement Idea: Open Notebook listing of notebooks needs to be easier to navigate with many notebooks

[BrianAdams]

The short comings in the current UI:

• Full names of the notebooks are missing in the list of notebooks and you have to click on the actual one to see the full name to populate the full disk path of the livebook.

Quick Suggestions:

• List the notebooks 1 per line so you can see the full name when browsing
• Add a filter option so that you can see all livebooks with "XYZ" in the name of the livebook.

[jonatanklosko]

Hey @BrianAdams, good suggestions, implemented in #2932. I don't think we should list one file per line, because the tradeoff is that the user sees less files and needs to scroll. That said, I changed the number of columns, so the maximum is 3, which gives each file more space.