use "=" for dependencies to ensure exactly equal version

...so that things don't break when projects change.

package.json

@@ -56,15 +56,15 @@
     "binary": "=0.3.0",
     "step": "=0.0.4",
     "buffers": "=0.1.1",
-    "buffertools": "~2.0.1",
-    "browserify": "~3.32.1",
-    "browser-pack": "~2.0.1",
-    "commander": "~2.1.0",
+    "buffertools": "=2.1.2",
+    "browserify": "=3.40.0",
+    "browser-pack": "=2.0.1",
+    "commander": "=2.1.0",
     "browserify-bignum": "git://github.com/maraoz/browserify-bignum.git",
     "browserify-buffertools": "git://github.com/maraoz/browserify-buffertools.git",
-    "brfs": "~1.0.0",
-    "chai": "~1.9.0",
-    "uglifyify": "~1.2.3"
+    "brfs": "=1.0.0",
+    "chai": "=1.9.1",
+    "uglifyify": "=1.2.3"
   },
   "devDependencies": {
     "grunt-contrib-watch": "~0.5.3",