fix(versionning): Fix version

Version should be x.y.z for releases. It makes things homogenous for
debian version (that needs a number as first char) and it is
semantically better.

At this time, the Makefile is OK. Maybe we don't need `PKG_VERSION`
later.

generator/version.go

@@ -1,8 +1,8 @@
 package generator
 
 import (
+	"regexp"
 	"runtime/debug"
-	"strings"
 )
 
 // Version is the version of katenary. It is set at compile time.
@@ -12,13 +12,19 @@ var Version = "master" // changed at compile time
 // the version is set at compile time for the github release. But, it the user get
 // katneary using `go install`, the version should be different.
 func GetVersion() string {
-	if strings.HasPrefix(Version, "release-") {
+	// try to get the semantic version from the Version variable (theorically set at compile time)
+	reg := regexp.MustCompile(`^(.?\d+.\d+.\d+.*)|^release-.*`)
+	if reg.MatchString(Version) {
 		return Version
 	}
-	// get the version from the build info
+
+	// OK... let's try to get the version from the build info
+	// get the version from the build info (when installed with go install)
 	v, ok := debug.ReadBuildInfo()
 	if ok {
 		return v.Main.Version + "-" + v.GoVersion
 	}
+
+	// OK... none worked, so we return the default version
 	return Version
 }