Autotune directory server to use a greater number of files

This changes the system limits for the dirsrv user as well as
configuring DS to allow by default 8192 max files and 64 reserved
files (for replication indexes, etc..).

Fixes: https://fedorahosted.org/freeipa/ticket/464

install/share/Makefile.am

@@ -17,6 +17,7 @@ app_DATA =				\
 	default-keytypes.ldif		\
 	default-pwpolicy.ldif		\
 	delegation.ldif			\
+	ds-nfiles.ldif			\
 	dns.ldif			\
 	kerberos.ldif			\
 	indices.ldif			\