- Add timeout_heap_get_size() to get active timer count
- Add global counters in memory_pool: g_total_free and g_total_allocated
- Simplify busy memory calculation to single formula:
busy = memory_pool_get_total_allocated() - memory_pool_get_total_free_blocks()
- Add new IDC_EDIT_ACTIVE_TIMEOUTS and IDC_EDIT_BUSY_MEMORY to GUI