Reorder clauses as suggested by Alisdair

Author: jaredhoberock

main.html

@@ -12,8 +12,8 @@
 <cxx-include href="normative_references.html"></cxx-include>
 <cxx-include href="terms_and_definitions.html"></cxx-include>
 <cxx-include href="general.html"></cxx-include>
-<cxx-include href="execution_policies.html"></cxx-include>
 <cxx-include href="exceptions.html"></cxx-include>
+<cxx-include href="execution_policies.html"></cxx-include>
 <cxx-include href="algorithms.html"></cxx-include>
 <cxx-include href="task_block.html"></cxx-include>
 <cxx-include href="data_parallel_types.html"></cxx-include>