Add record of sent and received links

[shepazu]

• [x] Keep a list of all links created and received
  • [x] Provide a clear option not to save links (opt-in or opt-out?)
• [x] Store in localStorage
  • [ ] Provide an option to store items locally (single-computer), or synced across Chrome instances (privacy concern, should add warning)
• [x] Present links as a set of lists in toolbar popup
  • [x] Separate lists for created and received
• [x] Make each item navigable
• [x] Maybe keep a count of each time visited?
• [x] Provide easy export option
• [x] Display how many stored nanotations apply to the current page in an icon badge
  • [x] Show all current-page nanotations in popup header
• [x] Allow user to search text of all nanotations in popup
• [x] Allow user to delete links
  • [x] Allow user to delete all links
  • [x] Allow user to delete selected links

[shepazu]

Making everything local like this, rather than server-based, allows it to be truly decentralized. This compensates for many of the limitations.

It might be interesting to make it easy to share exported links, as a JSON file, to be imported into someone else's instance.

[shepazu]

Added basic link storage in v0.5