Merge pull request #1439 from buildtesters/add_docs

docs on assert less than

docs/writing_buildspecs/performance_checks.rst

@@ -107,6 +107,7 @@ is compared with a reference value that can be useful when running performance c
 - :ref:`assert_ge`
 - :ref:`assert_gt`
 - :ref:`assert_le`
+- :ref:`assert_lt`
 - :ref:`assert_eq`
 - :ref:`assert_ne`
 - :ref:`assert_range`
@@ -174,6 +175,18 @@ In this example, we perform a **<=** operation, this can be done via ``assert_le
  :emphasize-lines: 37-46
  :linenos:
 
+.. _assert_lt:
+
+Less Than
+~~~~~~~~~~~
+
+In this example, we perform a **<** operation, this can be done via ``assert_lt`` property
+
+.. literalinclude:: ../tutorials/perf_checks/assert_lt.yml
+ :language: yaml
+ :emphasize-lines: 37-46
+ :linenos:
+
 .. _assert_eq:
 
 Assert Equal