Finish adding linters / linter cleanup

[tyler-smith]

In order to improve the overall quality of the repo, we are enabling the linter within travis but required our code to be made compliant with the lint rules before enabling each ruleset. Grouped by level of effort required.

The linter used by travis can be installed with curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | bash -s -- -b $GOPATH/bin v1.10 and executed using $GOPATH/bin/golangci-lint run. Linters may be enabled and disabled within .golangci.yml

Low

• [x] govet (#1166)
• [x] goconst (#1165)
• [x] ~goimports (#1156)~ We decided against requiring goimports have have relaxed this requirement.
• [ ] misspell (#1245) (https://github.com/OpenBazaar/openbazaar-go/compare/TS_mispell)

Medium (these are already in progress)

• [ ] megacheck (#1201) (https://github.com/OpenBazaar/openbazaar-go/compare/TS_megacheck)
• [ ] preallloc (#1202) (https://github.com/OpenBazaar/openbazaar-go/compare/TS_goprealloc)

High

• [ ] errcheck (#1203)
• [ ] golint (#1204)
• [ ] unconvert (#1205)

[cpacia]

Is this completely done?

[placer14]

Not yet. I updated it to be current.

[ulshell]

I want to work on this

[tyler-smith]

@ulshell That'd be great, thanks. A good place to start is probably finishing up megacheck or prealloc. I have them started but havn't had time to finish them.

Megacheck branch Prealloc branch