Cleanup (#197)

* Removed unused code
* Use cclog for logging
* Wrap errors so that they can be unwrapped
* Revert wrong use of slices.Delete()
* Fix derivative values should be float
* Suggestions from the gocritic linter
* Fixed: interface method AddChannel must have all named params (inamedparam)
* Enable linter: errorlint
* Replace fmt.Sprintf("%d", i)) by strconv.Itoa(i) for improved performance
* Correct misspelled words
* Break up very long lines into multiple lines
* lp.NewMessage -> lp.NewMetric
* Preallocate slices of known length

collectors/sampleTimerMetric.go

@@ -37,11 +37,11 @@ type SampleTimerCollector struct {
 }
 
 func (m *SampleTimerCollector) Init(name string, config json.RawMessage) error {
-	var err error = nil
+	var err error
 	// Always set the name early in Init() to use it in cclog.Component* functions
 	m.name = "SampleTimerCollector"
 	// This is for later use, also call it early
-	if err := m.setup(); err != nil {
+	if err = m.setup(); err != nil {
 		return fmt.Errorf("%s Init(): setup() call failed: %w", m.name, err)
 	}
 	// Define meta information sent with each metric