Script to automate setting+tagging version name

Hello,

At the moment, while Express version 3.3.2 and version 3.3.3 are out in the npm registry, those versions are not tagged in the Git repository. Tags may be "annoying to maintain" (please note the official quote ;-) ) when they are not part of an automated process.

So here I propose you a script to ease version name bump and tag.

Please note that this script enforces the SemVerTag sub-spec (because this is the convention I use for the projects I work on and from where this script is coming):
version names are like "3.3.4" (semver compliant) and that tag names are like "v3.3.4".

Also note that recently the SemVerTag sub-spec has been removed from the SemVer spec but only to have the SemVer reach the widest possible consensus https://github.com/mojombo/semver.org/issues/42 but SemVerTag is still relevant and useful cf. http://stackoverflow.com/questions/2006265/is-there-an-standard-naming-convention-for-git-tags

If following SemVerTag is not what you want, I can modify the script so that version names and version tags are of the same form. Please let me know.

Best, (and thank you for Express!)