recognise UNLICENSE/UNLICENCE .md/.txt/<empty> license files

Author: Challanger524

styles/components/icons/mapping.less

@@ -711,6 +711,12 @@
 .icon-partial("LICENCE.txt", "license", @yellow);
 .icon-partial("LICENSE.md", "license", @yellow);
 .icon-partial("LICENCE.md", "license", @yellow);
+.icon-partial("UNLICENSE", "license", @yellow);
+.icon-partial("UNLICENCE", "license", @yellow);
+.icon-partial("UNLICENSE.txt", "license", @yellow);
+.icon-partial("UNLICENCE.txt", "license", @yellow);
+.icon-partial("UNLICENSE.md", "license", @yellow);
+.icon-partial("UNLICENCE.md", "license", @yellow);
 .icon-partial("COPYING", "license", @yellow);
 .icon-partial("COPYING.txt", "license", @yellow);
 .icon-partial("COPYING.md", "license", @yellow);