Make dogtag an optional (and default un-) installed component in a replica.

A dogtag replica file is created as usual. When the replica is installed
dogtag is optional and not installed by default. Adding the --setup-ca
option will configure it when the replica is installed.

A new tool ipa-ca-install will configure dogtag if it wasn't configured
when the replica was initially installed.

This moves a fair bit of code out of ipa-replica-install into
installutils and cainstance to avoid duplication.

https://fedorahosted.org/freeipa/ticket/1251

install/tools/man/Makefile.am

@@ -12,6 +12,7 @@ man1_MANS = 				\
 	ipa-server-certinstall.1	\
 	ipa-server-install.1		\
 	ipa-dns-install.1		\
+	ipa-ca-install.1		\
 	ipa-ldap-updater.1		\
 	ipa-compat-manage.1		\
 	ipa-nis-manage.1		\