Update code and tests post a linting check.

[ozym]

golangci-lint run -E gosec

Spotted one error related to reuse of a variable, but mostly error handling in tests and deadcode.

@danieldooley @junghao could you have a look through at some point. The only outstanding warning is about the last few lines of tools/sit/main.go (error handling in the "verbose" part).

[junghao]

Looks good. But TravisCI has problem in testing?
And do you want to add golangci-lint to .travis.yml ?

[ozym]

Thanks @junghao just waiting on getting the code valid first before adding to travis. That will be the next step after all the code passes muster. Kicked travis to re-run the checks and it seems to have come back.

[junghao]

Looks good

[danieldooley]

@ozym hope you don't mind, I've fixed the tools/sit linting and enabled the linter in the travis build

[ozym]

@danieldooley no problems, will need to be reviewed / ticked again.