Added XPATH variable and correction changes

Changes:

    - Added XPATH and variables for Network, Error logs, inventory and LED's, Firmware and  Power headings.
    - Changed XPATH names as per gui/data/gui_variables.py

Tested:
    - Ran successfully gui/data/gui_variables.py
    - Ran successfully gui/gui_test/gui_header/test_gui_header.robot
    - Ran successfully gui/gui_test/overview_menu/test_overview_menu.robot

Change-Id: I84f7fd7a8c9862a0e770e2b8d11d503b7bbc82eb
Signed-off-by: rramyasr-in <rramyasr@in.ibm.com>
diff --git a/gui/gui_test/gui_header/test_gui_header.robot b/gui/gui_test/gui_header/test_gui_header.robot
index 375564e..d4b9f83 100644
--- a/gui/gui_test/gui_header/test_gui_header.robot
+++ b/gui/gui_test/gui_header/test_gui_header.robot
@@ -29,7 +29,7 @@
 
     Wait Until Element Is Visible   ${xpath_server_health_header}
     Click Element  ${xpath_server_health_header}
-    Wait Until Page Contains Element  ${xpath_event_header}  timeout=15s
+    Wait Until Page Contains Element  ${xpath_event_logs_heading}  timeout=15s
 
 
 Verify Server Power Button