Merge pull request #563 from ARMmbed/itm-docs

Minor tweaks on ITM docs regarding branding

Author: Amanda Butler

docs/reference/contributing/target/itm.md

@@ -1,6 +1,6 @@
-<h2 id="itm-port">Instrumented Trace Macrocell</h2>
+<h2 id="itm-port">Instrumentation Trace Macrocell</h2>
 
-For targets with Arm CoreSight (for example, Cortex-M3 and Cortex-M4), the Instrumented Trace Macrocell provides a lightweight, nonintrusive way to collect debug trace output.
+For targets with Arm [CoreSight](http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0314h/) (for example, Cortex-M3 and Cortex-M4), the Instrumentation Trace Macrocell (ITM) provides a lightweight, nonintrusive way to collect debug trace output.
 
 ### Assumptions