Add syntax highlighting test file for INI (#1213)

tests/syntax-tests/source/INI/test.ini

@@ -0,0 +1,18 @@
+[section]
+key=value
+numeric = 42
+quotes="this value is quoted"
+quotes2="this is not a comment ;foo"
+different_quotes='these are other characters'
+
+[another one]
+first = value
+; comment on own line
+;another one
+second=value ; comment at the end of a line
+third = value;another one
+# is this a comment? maybe.
+
+[section.with.dots]
+[section\with\backspaces]
+[section;with;semicola]