3.1.0

Changes

• Change format of all navigation types. Possible breaking change, please check format below
  Before, navigation for header and footer was using a simple key value list, this has been now changes to the following:

  navigation_header:
  - title: Home
    url: /
  - title: Elements
    url: /elements/
  

  This is to allow for more customisation by the person using the theme and better clarity in the codebase. For more verbose examples check the config file
• Improved format for sharing nav. Items can either have a colour value to colour the button or just true to make it appear with a default button colour
• Updated README.md to ensure sharing nav has been documented correctly
• Remove commented sharing nav items for cleaner presentation
• Remove bundler from dependencies. Bundler is not needed within the gem itself, just to install the gem into the project it's being used within