Make createItems more resilient to crash exceptions

The createItems function was updated to get around some problematic crash exceptions I ran into during updates.  The following is a summary of the changes:

* A Warnings counter per list was added to track warnings during the items linking phase.  

* A Warning Counter Summary dumped at the end.  The following is a sample output of the counter at the end:

    Successfully created:

    ...
    *   1 AAA
         **0 warnings**

    *   1 BBB
         **1 warnings**
    ...

* Checks where added to prevent run-time exceptions.  Instead, the exceptions are logged.  Some were harmless.

* The following is a sample generated warning:

    **APP-NAME: WARNING:  Invalid relationship(undefined reference list) [list: THE-LIST] [path: THE-PATH]**

* An internal writeLog function was created to centralize createItems logging.  Did this because I wanted to differentiate logging for different vhost all coming up in parallel.  As you can see in #4 above the keystone.get('name') property is prepended to the logs.


Feel free to tweak as you see fit.  It did solve my issues and provides better feedback!

Let's only add warnings if there are any.