API specification changes

[khuck]

• - need API call to get active list of PAPI counters, count (for policies)
• - what if a policy wants to change/add PAPI counters? need an API call for that.
• - environment variables - add apex_disable, apex_suspend, apex_api_suspend
• - remove argc,argv version of apex_init. it is only used for TAU initialization. We can fake that by getting the command line from /proc
• - spell check
• - registering a thread no longer starts a timer. Should it for HPX3? It should be a metadata field if TAU is used.
• - changing behavior of print_options to get_options
• - need to document the get/set methods for the environment variables?
• - change return type of apex::start to apex_profiler_handle
• - change argument type of apex::stop to apex_profiler_handle
• - thread states - do we need waiting and blocked?
• - register policy returns apex_policy_handle, not a *
• - register policy needs a C API
• - should get_profile return a copy of the profile state? currently it returns live data.
• - setup_power_cap_throttling should be removed (or not exported), and should be executed when the APEX_THROTTLE_ENERGY environment variable is set
• - get_tunable_parameters should be removed
• - setup_custom_tuning has changed - it has different arguments. The new signature is in apex_api.hp
• - apex_shutdown_throttling should be not public
• - Still need to review the OCR/Legion API calls.