Improved iterator support for GHashTable
Add more iterator support, mainly with three new functions:
g_hash_table_iter_get_key_value()
g_hash_table_lookup_iter()
g_hash_table_insert_iter()
This links to issue #613
Add more iterator support, mainly with three new functions:
g_hash_table_iter_get_key_value()
g_hash_table_lookup_iter()
g_hash_table_insert_iter()
This links to issue #613