[extension] move check processing to its own method
[extension] check extensions, standalone scheduling, gc metrics
[extension] test standalone check extensions
[extension] check request publishing for check extensions
[extension] adjusted log lines for consistency
[extension] test check extension request scheduling, extension require needs expanded path
[extension] no gc profiler for ruby < 1.9.3
[extension] updated changelog
[extension] changelog edit
Merge pull request #473 from portertech/extension

Check extension support
[hacks] cached handler list -> handlers, improved throughput
[hacks] cleaned up config validation
[hacks] remove handler list cache, unknown handler log lines are important
[hacks] fixed nested set validation
[hacks] dont enforce the use of a config file or config dir
[hacks] made client check extensions a bit more robust
[hacks] client socket handler uses reply (bool) instead of protocol
[hacks] removed check extension run rescue, almost useless, threads man
[hacks] ensure check extension intervals are integers
[hacks] style change, push() is now <<