Merge pull request #18 from wanelo-chef/composite-metrics

Composite metrics
rescue timeout and connrefused errors for JSON, Resmon, and NAD by returning empty metrics lists, instead of terminating Chef
properly scope variable with target's response outside the begin block
Merge pull request #20 from jsime/resmon-exception

Resmon/NAD/JSON target exception handling
Fix syntax error
Merge branch 'master' into wanelo