Changes fall into one of the following:
- gofmt -s
- receiver name is inconsistent
- omit unused 2nd value from range
- godoc comment formed incorrectly
- err assigned and not used
- if block ends with a return statement followed by else
As pointed out by the linter, some exported functions and types are
missing doc comments.
The linter warnings have been reduced from 194 to 116.
Not all missing comments have been added in this commit though.
