Indigo v1.3.0 released

Indigo v1.3.0 is a minor release that brings Indigo into better compliance with Hugo theme guidelines.

From the changelog:

Added

• Adds a mainSection configuration parameter to set preferred content name.

Changed

• Updated CONTRIBUTING.md to reflect new contributions process.
• Bumped the minimum Hugo version requirement to 0.58 to account for breaking changes to list pages.

Fixed

• As part of an audit of the theme’s code:
  • Removed forward slashes (/) in URLs for better compatibility with sites that don’t live at a domain root.
  • Fixed the location from which the theme’s fonts are loaded.

Removed

• GitHub issue and pull request templates removed from the repo.