Make the installer/uninstaller more aware of its state

We have had a state file for quite some time that is used to return
the system to its pre-install state. We can use that to determine what
has been configured.

This patch:
- uses the state file to determine if dogtag was installed
- prevents someone from trying to re-install an installed server
- displays some output when uninstalling
- re-arranges the ipa_kpasswd installation so the state is properly saved
- removes pkiuser if it was added by the installer
- fetches and installs the CA on both masters and clients

install/tools/ipa-server-install

@@ -375,7 +375,7 @@ def check_dirsrv(unattended):
             print "\t636"
         sys.exit(1)
 
-def uninstall(ca=False, dm_password=None):
+def uninstall(dm_password=None):
     if dm_password:
         api.Backend.ldap2.connect(bind_dn="cn=Directory Manager", bind_pw=dm_password)
 
@@ -387,13 +387,9 @@ def uninstall(ca=False, dm_password=None):
         pass
 
     ntpinstance.NTPInstance(fstore).uninstall()
-    if ca:
-        try:
-            from ipaserver.install import cainstance
-        except ImportError:
-            print >> sys.stderr, "Import failed: %s" % sys.exc_value
-            sys.exit(1)
+    if cainstance.CADSInstance().is_configured():
         cainstance.CADSInstance().uninstall()
+    if cainstance.CAInstance().is_configured():
         cainstance.CAInstance().uninstall()
     bindinstance.BindInstance(fstore).uninstall()
     httpinstance.HTTPInstance(fstore).uninstall()
@@ -455,6 +451,8 @@ def main():
     else:
         standard_logging_setup("/var/log/ipaserver-install.log", options.debug)
         print "\nThe log file for this installation can be found in /var/log/ipaserver-install.log"
+        if dsinstance.DsInstance().is_configured() or cainstance.CADSInstance().is_configured():
+            sys.exit("IPA server is already configured on this system.")
 
     global fstore
     fstore = sysrestore.FileStore('/var/lib/ipa/sysrestore')
@@ -496,7 +494,7 @@ def main():
                         sys.exit("\nUnable to connect to LDAP server %s" % api.env.host)
                     conn.disconnect()
 
-        return uninstall(not certs.ipa_self_signed(), dm_password)
+        return uninstall(dm_password)
 
     # This will override any settings passed in on the cmdline
     options._update_loose(read_cache())