rename pattern rule files

src/rules/pattern.h

@@ -0,0 +1,25 @@
+#ifndef __tree_sitter_pattern_h_
+#define __tree_sitter_pattern_h_
+
+#include "rule.h"
+
+namespace tree_sitter {
+    namespace rules {
+        class Pattern : public Rule {
+        public:
+            Pattern(const std::string &string);
+            TransitionMap<Rule> transitions() const;
+            bool operator==(const Rule& other) const;
+            std::string to_string() const;
+            rule_ptr to_rule_tree() const;
+        private:
+            const std::string value;
+        };
+
+        typedef std::shared_ptr<const Pattern> pattern_ptr;
+        pattern_ptr pattern(const std::string &value);
+    }
+}
+
+#endif
+