Faster tagging and reading in Bookmarks

Added to Bookmarks:

• Tags as chips. Type a tag and press Enter; tags already in use are offered as you type, with how many bookmarks have each.
• Suggested tags. When you add a bookmark, and on its page, Magpie suggests the tags on your other bookmarks from the same site and existing tags that appear in the title. The bookmark you just saved shows them on its row. A suggestion is only added when you choose it.
• Tags as filters. Tags are listed under the search field with counts, as in Password Vault. Choose one to narrow the list; choose another to narrow it further.
• Add tag for several bookmarks at once takes a new tag as well as one in use.
• Display shows the list as a compact list, a list with previews, or cards with images, and remembers your choice.
• Keyboard shortcuts, the same as RSS Reader where they overlap: j and k to move, o to open, v for the original, m read, f favorite, e archive, x select, t tags. Press ? for the list.
• Mark read and open next at the end of Reader view.
• RSS Reader: follow a bookmarked site from the bookmark's More menu, and entries you have already saved show Saved in Bookmarks.
• Collection feeds. An unlisted or public collection has an RSS feed of its links.