Significantly improve CPU and memory usage when not using SSA-powered linters.
Improve readability of go/packages errors.
Improve debugging capabilities and write doc about debugging.
This updates the unparam linter to the current version that has fewer
false positives. The go.{mod,sum} files and the vendor folder are
updated as follows:
export GO111MODULE=on
go get -u mvdan.cc/unparam
go mod tidy
go mod vendor
The unparam callgraph algorithm is no longer selectable. Ref:
https://github.com/mvdan/unparam/commit/e6a6d1c5
This is the reason for removing the c.CallgraphAlgorithm(us.Algo) line
from pkg/golinters/unparam.go.
