SCSS-Lint 0.36.0

Includes a few changes to exit codes returned by scss-lint in special conditions. One new linter to look out for is the PropertyUnits linter, which allows you to enforce the kind of units you allow on certain properties throughout your SCSS code.

• Fix SpaceAfterPropertyColon to report nested properties
• Add PropertyUnits allowing customization of which units are allowed for specific properties
• Allow color literals in map declarations and the rgba helper function in ColorVariable
• Gracefully handle when a library specified via -r/--require is not found
  and return a semantic exit code EX_UNAVAILABLE (69)
• Improve message of DeclarationOrder to specify the line number of the
  out-of-order item and the line number of where it was expected to be
• Return helpful error message and unsuccessful exit code when all files matched by specified glob patterns are excluded by --exclude flags and
  exclude configuration settings * Change exit code returned when file globs patterns did not match any files to
  be different from the exit code returned when a specified file does not exist