devkit: Release 0.7.0.

amberc / amberc task: Libraries are AMD modules;
no need to put them in dependency order.
config.js can be reused in Gruntfile.js to set mappings
for amberc / amberc grunt task.

external/amber-dev/package.json

@@ -1,6 +1,6 @@
 {
   "name": "amber-dev",
-  "version": "0.6.1",
+  "version": "0.7.0",
   "description": "Development goodies for Amber Smalltalk",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1"