Global manifest structure

The global manifest is a JSON file that stores the list of distributions, release versions, and basename of the distributions manifest file. This is read at the creation of the ManifestImporter object in order to prepare for the import of a distributions manifest file.

Example creation of the ManifestImporter object.

    def main():
        mi = ManifestImporter()
        print mi.global_manifest

    if __name__ == "__main__":
    main()

JSON Format of manifest.global:

    {
	"<distribution_name>":{
		"release":["<version>"],
		"manifest":"<manifest basename>"
		}
    }

Example manifest.global with only a ubuntu entry:

   {
        "ubuntu":{
		"release":["10.04","10.10"],
		"manifest":"manifest.ubuntu."
		}
    }