[log] Add messages at start of instrumentation.
[log] Add messages at start of instrumentation.

fhijaz/Graphite,8l/Graphite,mit-carbon/Graphite,mit-carbon/Graphite-Cycle-Level,mit-carbon/Graphite-Cycle-Level,mit-carbon/Graphite,fhijaz/Graphite,nkawahara/Graphite,fhijaz/Graphite,mit-carbon/Graphite-Cycle-Level,nkawahara/Graphite,mit-carbon/Graphite,8l/Graphite,nkawahara/Graphite,mit-carbon/Graphite,victorisildur/Graphite,fhijaz/Graphite,victorisildur/Graphite,8l/Graphite,mit-carbon/Graphite-Cycle-Level,victorisildur/Graphite,nkawahara/Graphite,8l/Graphite,victorisildur/Graphite