Description of problem:

Using the searchbar and searching for things via a datetime and using the 'is' operator does not return the expected results.

Version-Release number of selected component (if applicable):

develop

How reproducible:

Always

Steps to Reproduce:
1. Search for something with a datetime (i.e System/LastInventoried)
2. use the 'is' operator
3. 

Actual results:

Nothing returned

Expected results:

The systems that were inventoried on that date

Additional info:

I replicated this problem with MariaDB 5.5.31.
The problem is with comparing datetime values as strings.

This is the crucial part of the query:

  system.date_lastcheckin >= "2013-08-28 00:00:00" AND system.date_lastcheckin <= "2013-08-29 23:59:99"

Specifically, the '<=' doesn't seem to work as we expect. Replacing it with the following, fixes the problem:

  system.date_lastcheckin >= "2013-08-28 00:00:00" AND system.date_lastcheckin <= STR_TO_DATE('2013-08-28 23:59:59', '%Y-%m-%d %H:%i:%s')