Add npm script for safe release publish

Npm publishes all versions with `latest` tag by default. This means that even
versions like `1.1.0-alpha1` will be considered latest by npm and will be
installed by default when typing `npm install neo4j-driver`.

This commit adds a safe publish plugin that will publish versions that consist
of three numbers (like `X.Y.Z`) with `latest` tag and versions that contain
hyphen (like `X.Y.Z-betaAB`) with tag `next`. Users will be able to try out
pre-released driver versions using `npm install neo4j-driver@next`.

Author: lutovich

package.json

@@ -14,7 +14,8 @@
     "start-neo4j": "gulp start-neo4j",
     "stop-neo4j": "gulp stop-neo4j",
     "run-tck": "gulp run-tck",
-    "docs": "esdoc -c esdoc.json"
+    "docs": "esdoc -c esdoc.json",
+    "publishRelease": "npm-publish-safe-latest next"
   },
   "main": "lib/index.js",
   "devDependencies": {
@@ -42,6 +43,7 @@
     "jasmine-reporters": "^2.0.7",
     "merge-stream": "^1.0.0",
     "minimist": "^1.2.0",
+    "npm-publish-safe-latest": "^1.1.6",
     "phantomjs-prebuilt": "^2.1.7 ",
     "run-sequence": "^1.1.4",
     "through2": "~2.0.0",