Ticket 47620 - Fix logically dead code.

Coverity issues:  12419 & 12420

https://fedorahosted.org/389/ticket/47620

Reviewed by: rmeggins(Thanks!)
(cherry picked from commit 080cb44f5eaa794375a8e69b6e1ac09fcae9a961)
Ticket 47627 - Fix replication logging

We printed the same CSN for the missing CSN and the supplier min CSN because
we reused the same CSN pointer.

https://fedorahosted.org/389/ticket/47627

Reviewed by: rmeggins(Thanks!)
(cherry picked from commit 20cccf58108099cead2412a979e70e4f5972b806)
Ticket #47606 - replica init/bulk import errors should be more verbose

Description:
1. maxbersize: If the size of an entry is larger than the consumer's
   maxbersize, the following error used to be logged:
     Incoming BER Element was too long, max allowable is ### bytes.
     Change the nsslapd-maxbersize attribute in cn=config to increase.
   This message does not indicate how large the maxbersize needs to be.
   This patch adds the code to retrieve the failed ber size.
   Revised message:
     Incoming BER Element was @@@ bytes, max allowable is ### bytes.
	 Change the nsslapd-maxbersize attribute in cn=config to increase.
   Note: There is no lber API that returns the ber size if it fails to
   handle the ber.  This patch borrows the internal structure of ber
   and get the size.  This could be risky since the size or structure
   of the ber could be updated in the openldap/mozldap lber.
2. cache size: The bulk import depends upon the nsslapd-cachememsize
   value in the backend instance entry (e.g., cn=userRoot,cn=ldbm
   database,cn=plugins,cn=config).  If an entry size is larger than
   the cachememsize, the bulk import used to fail with this message:
     import userRoot: REASON: entry too large (@@@ bytes) for the
	 import buffer size (### bytes).  Try increasing nsslapd-
	 cachememsize.
   Also, the message follows the skipping entry message:
     import userRoot: WARNING: skipping entry "<DN>"
   but actually, it did NOT "skip" the entry and continue the bulk
   import, but it failed there and completely wiped out the backend
   database.
   This patch modifies the message as follows:
     import userRoot: REASON: entry too large (@@@ bytes) for the
	 effective import buffer size (### bytes). Try increasing nsslapd-
	 cachememsize for the backend instance "userRoot".
   and as the message mentions, it just skips the failed entry and
   continues the bulk import.
3. In repl5_tot_result_threadmain, when conn_read_result_ex returns
   non zero (non SUCCESS), it sets abort, but does not set any error
   code to rc (return code), which is not considered as "finished" in
   repl5_tot_waitfor_async_results and it contines waiting until the
   code reaches the max loop count (about 5 minutes).  This patch sets
   LDAP_CONNECT_ERROR to the return code along with setting abort, if
   conn_read_result_ex returns CONN_NOT_CONNECTED.  This makes the bulk
   import finishes quickly when it fails.

https://fedorahosted.org/389/ticket/47606

Reviewed by rmeggins@redhat.com (Thank you, Rich!!)
(cherry picked from commit 1119083d3d99993421609783efcb8962d78724fc)
(cherry picked from commit fde9ed5bf74b4ea1fff875bcb421137c78af1227)
Ticket 47620 - Fix dereferenced NULL pointer in agmtlist_modify_callback()

The server would dereference a NULL point if an attribute was deleted from a replication
agreement.

https://fedorahosted.org/389/ticket/47620

Reviewed by: rmeggins(Thanks!)
(cherry picked from commit 8baed897f504e75478b5dbbe736c1eaf6d2d7fa9)
Ticket 47620 - Fix missing left bracket

https://fedorahosted.org/389/ticket/47620
(cherry picked from commit 3a4d39e166449177c85b92af8b47c5c6848c4d02)