Move the yum object initialization to it's own function.

This is necessary so that we can get a pypungi object without having to
init the repositories.

src/bin/pungi.py

@@ -82,6 +82,8 @@ def main():
     mypungi = pypungi.Pungi(config, ksparser)
 
     if not opts.sourceisos:
+        if opts.do_all or opts.do_gather or opts.do_buildinstall:
+            mypungi._inityum() # initialize the yum object for things that need it
         if opts.do_all or opts.do_gather:
             mypungi.getPackageObjects()
             mypungi.downloadPackages()

src/pypungi/__init__.py

@@ -129,10 +129,13 @@ class Pungi(pypungi.PungiBase):
         self.srpmlist = []
         self.debuginfolist = []
         self.resolved_deps = {} # list the deps we've already resolved, short circuit.
-        self.repos = []
-        self.mirrorlists = []
+
+    def _inityum(self):
+        """Initialize the yum object.  Only needed for certain actions."""
 
         # Create a yum object to use
+        self.repos = []
+        self.mirrorlists = []
         self.ayum = PungiYum(config)
         self.ayum.doLoggingSetup(6, 6)
         yumconf = yum.config.YumConf()