Cleaned up the perf_event class
Callchain access, plus more perf cleanup
Separated output code
Working per-thread perf_event processing
Forgot to save
Added test and bench targets to benchmarks
Small adjustments, plus forgotten changes in profiler.cpp
Handle sampling signals on stack. Seems to help with pbzip2's lost signal problem
Removed function template wrapper, since it allocates memory (not safe in a signal handler). Counter backoff is in progress.

--HG--
rename : lib/support/libsuport.cpp => lib/support/libsupport.cpp
Fixed extra timing handling, plus more concise thread communication via mutex/cond_var
Interposition was broken.