fix #273: fix logical issues in adding/removal of file watchers
update version.txt to 0.2.5
fix #274: av during graceful process recycle
fix #275: refactor graceful recycling logic to avoid deadlock potential
update version to 0.2.6
fix #276: av when generating iisnode-debug header during process recycling
fix #278: ref counting and error handling cleanup during recycle
fix regression in 109_hello_world_debug
fix #277: deadlock in iisnode-debug header generation during recycle