Add files for UPM

.npmignore

+/ImageTemplates*
+/PostProcessing*
+/SampleScenes*
+/TestbedPipelines*
+/Tests*
+/.collabignore
+/.gitignore
+/.gitmodules
+/SRPMARKER*

package.json

+{
+	"name": "com.unity.render-pipelines",
+	"version": "0.1.0",
+	"unity": "2017.3",
+	"description": "Render pipelines using SRP",
+	"dependencies": {
+	}
+}

package.json.meta

+fileFormatVersion: 2
+guid: 069bb024a0bb04a43a3049c4339ebdb5
+timeCreated: 1504187325
+licenseType: Pro
+TextScriptImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: