Adds a panel on the right that displays all the tags you have, along with their tag count.

When clicking on a tag, a search for the tag is activated. To ==toggle a tag== in search, Ctrl-click it instead.

Sorting

The tags are sorted from most frequently used to least frequently used. You can change the sort order to alphabetical or reverse it.

Nested tags

If you write your tags like #inbox/to-read and #inbox/processing, you can enable "show nested tags" to view them as a tree instead of a flat list.

Under the default flat view, the tag pane will look like:

- inbox/to-read
- inbox/processing

Under the nested tag view, the tag pane will look like:

- inbox
	- to-read
	- processing