mtapi_cpp: improved documentation of default values and priorities

mtapi_cpp/include/embb/mtapi/execution_policy.h

@@ -37,6 +37,10 @@ namespace mtapi {
  *  - the affinity of tasks to MTAPI worker threads (not CPU cores) and
  *  - the priority of the spawned tasks.
  *
+ * The priority is a number between 0 (denoting the highest priority) to
+ * max_priorities - 1 as given during initialization using Node::Initialize().
+ * The default value of max_priorities is 4.
+ *
  * \ingroup CPP_MTAPI
  */
 class ExecutionPolicy{

mtapi_cpp/include/embb/mtapi/node.h

@@ -54,7 +54,14 @@ namespace mtapi {
 class Node {
  public:
   /**
-    * Initializes the runtime singleton using default values.
+    * Initializes the runtime singleton using default values:
+    *   - all available cores will be used
+    *   - maximum number of tasks is 1024
+    *   - maximum number of groups is 128
+    *   - maximum number of queues is 16
+    *   - maximum queue capacity is 1024
+    *   - maximum number of priorites is 4.
+    *
     * \notthreadsafe
     * \throws ErrorException if the singleton was already initialized or the
     *         Node could not be initialized.