Description of problem:

When monitoring Apache server, SNMP doesn't have to be enabled (if URL is specified in Inventory -> Connection page) and it should be possible to remove SNMP Agent Host and Port values from JON UI for the selected Apache server.

However, the page cannot be saved if those values are not defined so the only way to disable SNMP would be to comment out the appropriate lines in the Apache's httpd.conf file.


Version-Release number of selected component (if applicable):
JON 2.4.1 

How reproducible:
every time

Steps to Reproduce:
1. Import and select Apache server (SNMP enabled);
2. Go to Inventory -> Connection page and press "Edit" button;
3. Check that the URL is properly specified;
3. Delete values for the "SNMP Agent Host" and "SNMP Agent Port" and press "OK" button;
  
Actual results:
The following messages are displayed: "SNMP Agent Host", a value is required." and "SNMP Agent Port", the value must be an integer." and the page cannot be saved.

Expected results:
It should be possible not to have "SNMP Agent Host" and "SNMP Agent Port" defined if the URL is specified as availability can be checked using that URL.