Bugfix: Correctly free old assignments when reloading

Fixes #516

include/data.h

@@ -148,7 +148,7 @@ struct Ignore_Event {
  *
  */
 struct regex {
-    const char *pattern;
+    char *pattern;
     pcre *regex;
     pcre_extra *extra;
 };

include/match.h

@@ -28,4 +28,10 @@ void match_copy(Match *dest, Match *src);
  */
 bool match_matches_window(Match *match, i3Window *window);
 
+/**
+ * Frees the given match. It must not be used afterwards!
+ *
+ */
+void match_free(Match *match);
+
 #endif

include/regex.h

@@ -17,6 +17,12 @@
  */
 struct regex *regex_new(const char *pattern);
 
+/**
+ * Frees the given regular expression. It must not be used afterwards!
+ *
+ */
+void regex_free(struct regex *regex);
+
 /**
  * Checks if the given regular expression matches the given input and returns
  * true if it does. In either case, it logs the outcome using LOG(), so it will