Version 1.2.0

This release comes with some new features, usability improvements and
a better build & release process.

Features:

• Documentation has been improved significantly, check out the new
  README and follow the links within!
• Extra variables can now be loaded from files on disk. Simply specify
  a list of YAML/JSON files under the 'import' key in your cluster
  context file. Check out #66 for details!
• Resource set paths can now be overridden by users. By default it is
  assumed that the path to a resource set is the same as its name,
  however this is now user-controllable.
  This means the same resource set can be included multiple times
  under different names, for easier including/excluding. See #71 for
  details!
• Kontemplate is currently getting a website that is under construction
  at kontemplate.works - feel free to check it out and
  give feedback!

Fixes:

• Windows release binaries now have the correct filename
• Several potential warning and error messages have been improved

Release binaries are signed with GPG key 66F505681DB8F43B which is
verified on my Github profile.