Add gometalinter to pre-commit hook

Enable varcheck and fix found issues

Add ineffassign to list of checks and fix found issues

Added nakedret and fixed found issues

Add interfacer check and fix found issue

Add lll and fix found issues

Add deadcode linter, remove unused code

pkg/fs/fakefile.go

@@ -31,11 +31,6 @@ type FakeFile struct {
 	open    bool
 }
 
-// makeFile makes a fake file.
-func makeFile() *FakeFile {
-	return &FakeFile{}
-}
-
 // makeDir makes a fake directory.
 func makeDir(name string) *FakeFile {
 	return &FakeFile{name: name, dir: true}