Force a rebuild during publication

This fixes an issue in which we released several builds (v2.1.3,
v2.0.4, and v2.0.3) with the wrong version number.  This happens when
we build, then tag, then release.

By forcing a rebuild at publication time, we make sure the build we
release has the right tag in it.

Issue #869

Change-Id: I23867ceef43162469c53006336b7f0226dbe16b6

package.json

@@ -45,6 +45,6 @@
   },
   "license": "Apache-2.0",
   "scripts": {
-    "prepublish": "in-publish && python ./build/checkversion.py && python ./build/all.py && python ./build/build.py --debug || not-in-publish"
+    "prepublish": "in-publish && python ./build/checkversion.py && python ./build/all.py --force && python ./build/build.py --force --debug || not-in-publish"
   }
 }