console error info not friendly

[ox123]

Issue Description

When I want to create a flow rules, when the dashboard can not connect to the sentinel core, it shows the bellow result
Type: bug report or feature request

Describe what happened (or what feature you want)

Describe what you expected to happen

How to reproduce it (as minimally and precisely as possible)

Tell us your environment

Anything else we need to know?

[cdfive]

I got this message when client application can't be connect:

Can you provide the error log of the dashboard?

[sczyh30]

@ox123 any feedback?

[brotherlu-xcq]

I reproduce this problem, when the update rules command executed timeout. The dashboard will show the message above. Need we update the failed message to a common message like Change the flowrules failed, Please check the dashboard log for more information. @sczyh30 @cdfive

[sczyh30]

Improvements are welcomed.

[brotherlu-xcq]

OK, I will try to improve it.