Add test to make sure it solves issue #10 as well

Author: sentinel-1

test/slugify_test.dart

@@ -32,6 +32,18 @@ void main() {
     expect(result, equals(expected));
   });
 
+  test('Non-english text (unicode): Example 1 Input from issue #10', () {
+    var result = slugify('ငယ်ငယ်ရွယ်ရွယ်နဲ့ ဆံပင်ဖြူခြင်း');
+    var expected = 'ငယငယရယရယန-ဆပငဖခင';
+    expect(result, equals(expected));
+  });
+
+  test('Non-english text (unicode): Example 2 Input from issue #10', () {
+    var result = slugify('बदले उसीएक् निर्माण करके(विशेष');
+    var expected = 'बदल-उसएक-नरमण-करकवशष';
+    expect(result, equals(expected));
+  });
+
   test('trims leading/trailing whitespace', () {
     var result = slugify('  too many spaces  ');
     var expected = 'too-many-spaces';