Fix two typos on tempest documentation

specifing => specifying
secion => section

Change-Id: Ie5c2ddb03586c780e4f338ba9dd2a8adbf824c6e
Closes-Bug: #1478941
diff --git a/README.rst b/README.rst
index af24569..d7063ba 100644
--- a/README.rst
+++ b/README.rst
@@ -107,7 +107,7 @@
 ----------
 
 Tempest also has a set of unit tests which test the Tempest code itself. These
-tests can be run by specifing the test discovery path::
+tests can be run by specifying the test discovery path::
 
     $> OS_TEST_PATH=./tempest/tests testr run --parallel