improve power route handler and error handling,

add test sim for bmc power sw

www/error_missing_requested_state.ssi

@@ -0,0 +1,4 @@
+{
+    "error": true,
+    "description": "Missing search parameter requested_state"
+}

www/error_requested_state_invalid.ssi

@@ -0,0 +1,4 @@
+{
+    "error": true,
+    "description": "Invalid requested_state must be 0 or 1"
+}