Add support for numerous links

[hawkins]

Currently, only 3 columns of up to 4 links are supported.

It would be ideal to have up to N columns of M links, where N and M can vary along some scale. Possibly limited by bootstrap widths of columns on a page.

[hawkins]

Would like to have a save pattern similar to the following:

[
  {
    "Social": [
      {"Facebook": "http://www.facebook.com/"},
      {"Twitter": "http://www.twitter.com"}
    ]
  },
  {
    "Some other header": [
      {"link title": "link address"},
      {...}, ...
    ]
  }
]

Essentially, an array of dictionaries (collections), where each collection dictionary maps a string (that collection's header) to an array of dictionaries (links), where these link dictionaries map a string (title) to another string (address).

Or similar. The important points here are these:

1. Collections are ordered
2. Links are ordered
3. Link titles are directly associated with their respective link addresses

As long as these goals are met and the function convertFromLegacy(version) is completed for converting from version 1.0 to version 1.3, this issue should be completed.