Clean up .robot files

  - Run rflint on .robot to ensure they conform to the standards.
    Fix the files that don't.
  - Add robot_custom_rules.py file for our repository custom rules.
  - run pycodestyle on new changes.

Change-Id: Idb2b895b81cb00220076a32b413e124980f4057b
Signed-off-by: Joy Onyerikwu <onyekachukwu.joy.onyerikwu@ibm.com>
diff --git a/robot_standards b/robot_standards
index 87b1196..415e769 100644
--- a/robot_standards
+++ b/robot_standards
@@ -4,3 +4,4 @@
 --ignore FileTooLong
 --ignore TooManyTestSteps
 --ignore TooManyTestCases
+--ignore InvalidTable