Move to setting version info explicitly in linker flags

We don't have go built-in VCS information in a nix build because the git
repository isn't present. After struggling to build an overlay that
would provide it, I decided this path is easier of just injecting in the
data that we need.

Issue: #5

api/version.go

@@ -0,0 +1,16 @@
+package api
+
+import (
+	"source.gleipnir.technology/Gleipnir/nidus-sync/version"
+)
+
+var (
+	versionInfo version.VersionInfo
+)
+
+func GetVersionInfo() version.VersionInfo {
+	return versionInfo
+}
+func SetVersionInfo(v version.VersionInfo) {
+	versionInfo = v
+}