Refactor: Safe version of g_hash_table_size() that checks for NULL first
Feature: Drop per-user core directories
Fix: Correctly stall the FSA when waiting for additional inputs
Refactor: IPC: Create a common wrapper for client connections

Reduces code duplication and will allow us to add event queues down the track.

Breaks API for IPC server functionality:
- crm_ipcs_send_ack()
- crm_ipcs_send()
- crm_ipcs_recv()
Log: Remove trace messgae
Log: Better trace logging for resources active at shutdown
Test: Fix ignore patterns for the Reattach test