Add clear functions to table and trie.

src/table.c

@@ -110,6 +110,9 @@ void libab_table_set_parent(libab_table* table, libab_ref* parent) {
     libab_ref_free(&table->parent);
     libab_ref_copy(parent, &table->parent);
 }
+void libab_table_clear(libab_table* table) {
+    libab_trie_clear(&table->trie);
+}
 void libab_table_free(libab_table* table) {
     libab_trie_foreach(&table->trie, NULL, compare_always,
                        _table_foreach_entry_free);

src/trie.c

@@ -110,6 +110,11 @@ int libab_trie_foreach(const libab_trie* trie, void* data, compare_func compare,
     return _libab_trie_foreach(trie->head, data, compare, foreach);
 }
 
+void libab_trie_clear(libab_trie* trie) {
+    libab_trie_free(trie);
+    libab_trie_init(trie);
+}
+
 void libab_trie_free(libab_trie* trie) {
     _libab_trie_free(trie->head);
     trie->head = NULL;