pb.FetchResponse -> metricData: extend metric's options
when copy metricData, copy all fields
Fix merge conflicts after 8827fe728ca12dba7a69f96bf60c8b1987cefa67
Merge branch 'cashlo-graph-support' into graph-support
gofmt++
Fix wrong printf verb (govet++)
marshalPNG() supports colors
make time labels depend on step size
PNG: support fgcolor and bgcolor
PNG: remove duplicated code + gofmt
implement drawAsInfinite