mark relative imports and ignore automatically

dependency/resolver.go

diff --git a/dependency/resolver.go b/dependency/resolver.go
index dc88f62..e3654d8 100644
--- a/dependency/resolver.go
+++ b/dependency/resolver.go
@@ -779,6 +779,8 @@
 	// Why does a Google product get a special case build mode with a local
 	// package?
 	LocAppengine
+	// LocRelative indicates the packge is a relative directory
+	LocRelative
 )
 
 // PkgInfo represents metadata about a package found by the resolver.
@@ -815,6 +817,12 @@
 		Name: name,
 	}
 
+	if strings.HasPrefix(name, "./") || strings.HasPrefix(name, "../") {
+		info.Loc = LocRelative
+		r.findCache[name] = info
+		return info
+	}
+
 	// Check _only_ if this dep is in the current vendor directory.
 	p = filepath.Join(r.VendorDir, filepath.FromSlash(name))
 	if pkgExists(p) {