Experimental support for mixins with interpolated selectors.
 interpolated mixins, fixed: possible false match if variable contains `,`
fixed merging of interleaved properties
merging of interleaved properties - fixed a typo in tests
Fix CHANGELOG broken link in README.
Merge pull request #1744 from jeffslofish/patch-1

Fix CHANGELOG broken link in README.
Merge pull request #1743 from seven-phases-max/property-merge-fix

Interleaved property merge fix
Merge pull request #1624 from seven-phases-max/mixins-with-interpolated-selectors

Experimental support for mixins with interpolated selectors
Added html files ending should be treated the same way as line endings
inside htm files.