The Rack handler should not output the body when dealing with HEAD requests
Rename some HttpServer fields for better clarity
Merge duplicate HTTP headers
Fix determining how many bytes an mbuf can contain
Introduce an admin command for freeing inactive mbufs, and show mbuf stats in server stats
Allow freeing spare client and spare request objects using an admin command
Add a low-level admin command for sending requests to admin servers directly
When invalidating a turbocache entry, invalidate the entries associated with the 'Location' and 'Content-Length' response headers too
Rename Passenger RackApp to Passenger RubyApp
Get rid of Base64.cpp in favor of mod_b64.cpp
Get rid of absolute_path in Passenger Standalone

It has been replaced by File.absolute_path_no_resolve.
Simulate EOF on rack.input when the request has no body.

This prevents app from trying to read from the socket when it is not allowed,
which would have interfered with keep-alive.
Fix compatibility of keep-alive with Rack socket hijacking
Minor refactoring
Prevent 'passenger-config install-standalone-runtime' from exiting prematurely