adding TestFiles to artifact config, transfers extra test files to VM

config/config.go

@@ -108,10 +108,18 @@ type PreloadModule struct {
 	TimeoutAfterLoad Duration
 }
 
+// Extra test files to copy over
+type FileTransfer struct {
+	User    string
+	Local   string
+	Remote  string
+}
+
 // Artifact is for .out-of-tree.toml
 type Artifact struct {
 	Name             string
 	Type             ArtifactType
+	TestFiles	 []FileTransfer
 	SourcePath       string
 	SupportedKernels []KernelMask