Merge branch 'master' into package-reorganization

# Conflicts:
#	com.unity.vfx-toolbox/package.json

com.unity.vfx-toolbox/package.json

+{
+  "name": "com.unity.vfx-toolbox",
+  "displayName": "VFX Toolbox",
+  "version": "1.0.0-preview",
+  "description": "Additional Tools for VFX Artists.\n\n* Image Sequencer\n* Houdini Exporters for Visual Effect Graph",
+  "keywords": [
+    "vfx",
+    "tools",
+    "flipbooks",
+    "visual",
+    "effects"
+  ],
+  "type": "tool",
+  "hideInEditor": false,
+  "unity": "2019.1"
+}