Created attachment 1065164 [details]
A screen shot that shows negative values in the graph

Description of problem:

When navigating to datasources "Connection Count" metric for EAP 5 in some cases graph will show negative values (from -1.0 up to 1.0) - see attached negativeValueGraph.png. The same will happen even when "Connection Count" is equal to 0. Only when value of this metric is > 0 proper graph values will be shown. 

This happens because JON does not take the measurement and data type into consideration. For example, for a trends ups measurement, the bottom value will never be lower then the minimum value. Therefore, it would make sense that we would start at 0 in this case. The opposite being true for trends down measurements. In those cases, the largest value on the y-axis should be the maximum value for the displayed time period.


Version-Release number of selected component (if applicable):
JBoss ON 3.3.2

How reproducible:
Always

Steps to Reproduce:
1. Start EAP 5, 
2. import EAP instance into JON inventory,
3. navigate to Monitoring page for EAP instance and open "Connection Count" metric graph;
4. Change the period for the graph to 6 months

Actual results:
Graph is shown with negative values on the y-axis although "Connection Count" cannot have negative value. 

Expected results:
Graph does not show negative values but starts from 0 (in this case).

Additional info: