update elements and fix some bugs

lib/src/prism/tests/languages/matlab/keyword_feature.test

Index: lib/src/prism/tests/languages/matlab/keyword_feature.test
diff --git a/lib/src/prism/tests/languages/matlab/keyword_feature.test b/lib/src/prism/tests/languages/matlab/keyword_feature.test
new file mode 100644
index 0000000000000000000000000000000000000000..c71e3f83a94070f09fc67e1faf708b0d42a4ad08
--- /dev/null
+++ b/lib/src/prism/tests/languages/matlab/keyword_feature.test
@@ -0,0 +1,21 @@
+break case catch continue
+else elseif end for
+function if inf NaN
+otherwise parfor pause
+pi return switch
+try while
+
+----------------------------------------------------
+
+[
+	["keyword", "break"], ["keyword", "case"], ["keyword", "catch"], ["keyword", "continue"],
+	["keyword", "else"], ["keyword", "elseif"], ["keyword", "end"], ["keyword", "for"],
+	["keyword", "function"], ["keyword", "if"], ["keyword", "inf"], ["keyword", "NaN"],
+	["keyword", "otherwise"], ["keyword", "parfor"], ["keyword", "pause"],
+	["keyword", "pi"], ["keyword", "return"], ["keyword", "switch"],
+	["keyword", "try"], ["keyword", "while"]
+]
+
+----------------------------------------------------
+
+Checks for all keywords.