Rename connection_handling.rb -> clear_query_cache_patch.rb

to make module name it defines.

Author: zdennis

lib/active_record_host_pool.rb

@@ -4,7 +4,7 @@
 require 'active_record/base'
 require 'active_record/connection_adapters/abstract_adapter'
 
-require 'active_record_host_pool/connection_handling'
+require 'active_record_host_pool/clear_query_cache_patch'
 require 'active_record_host_pool/connection_proxy'
 require 'active_record_host_pool/pool_proxy'
 require 'active_record_host_pool/connection_adapter_mixin'