make troubleshooting debug value more clear (#1114)

I was wondering if we should literally set `System.Debug` to `true` or if it was a variation of the capitalization. Lowercase "true" seems to work.

docs/troubleshooting.md

@@ -6,7 +6,7 @@ Often these logs are most relevant to the product but they can sometimes provide
 
 ## System.Debug
 
-If you are having issues with a build, the first step is to set System.Debug to true on the build definitions variables tab.  The agent and tasks will emit [debug]xxx lines for more detailed insight into what the specific task is doing.
+If you are having issues with a build, the first step is to set System.Debug to `true` on the build or release definitions variables tab.  The agent and tasks will emit [debug]xxx lines for more detailed insight into what the specific task is doing.
 
 ## Agent Trace Logs
 
@@ -100,4 +100,4 @@ Windows:
 Linux:
     export VSTS_HTTP_RETRY=5          // set http retry, valid range [5, 10]  
     export VSTS_HTTP_TIMEOUT=120      // set http timeout, valid range [100, 1200]  
-```
+```