Compile and lint issues

[meling]

I was trying to use gorename from VSCode the other day, but was blocked by some code in my GOPATH that turned out to be in the gotraining repo. Now, I updated the repo and the problem went away, but even after updating it appears there are still some compile and lint issues that you may want to take care of:

% golint ./...
2017/09/04 10:00:32 topics/go/language/methods/example5/example5.go:4:1: expected 'package', found 'import' (and 1 more errors)
main.go:17:5: exported var Render should have comment or be unexported
topics/go/concurrency/channels/example5/example5.go:18:7: var timeoutSeconds is of type time.Duration; don't use unit-specific suffix "Seconds"
topics/go/design/composition/exercises/template1/template1.go:109:6: expected operand, found '{' (and 1 more errors)
topics/go/design/error_handling/example1/example1.go:24:1: comment on exported function New should be of the form "New ..."
topics/go/design/error_handling/example1/example1.go:26:23: exported func New returns unexported type main.error, which can be annoying to use
topics/go/language/exporting/example3/counters/counters.go:12:21: exported func New returns unexported type counters.alertCounter, which can be annoying to use
topics/go/packages/context/exercises/template1/template1.go:71:3: expected '}', found 'return' (and 1 more errors)

[ardan-bkennedy]

This is going to happen :(. Not all the material can be lintable or buildable.