bump to 2.0.0-alpha7

Author: EzraBrooks

package.json

@@ -2,7 +2,7 @@
   "name": "roslib",
   "homepage": "https://robotwebtools.github.io",
   "description": "The standard ROS Javascript Library",
-  "version": "2.0.0-alpha6",
+  "version": "2.0.0-alpha7",
   "license": "BSD-2-Clause",
   "files": [
     "dist"