Added support for version ranges with basic operators:

v, err := semver.Parse("1.2.3")
range, err := semver.ParseRange(">1.0.0 <2.0.0 || >=3.0.0")
if range(v) {
    //valid
}

Introduce Make() which is an alias for Parse() and returns a version as value. New() changed to return a pointer.

Breaking changes:
Change New() to Make() to fix pointer vs value problem.

Breaking changes:
Changed from pointers to value arguments.
If this breaks your code, use latest stable v1 (tag:v1.1.0).
You could also use gopkg.in: go get http://gopkg.in/blang/semver.v1