Offline UI - indicate slow connection and failed credentials

[corinagum]

Resolves #1521

This adds a new component to the transcript that will notify the user when connectivity to the bot is taking longer than usual or has failed.
For slow connection, Web Chat will time 15 seconds before displaying the below warning:

A failed connection will be triggered when credentials are incorrect.

• Update Italian localization, courtesy of andreo
• @compulim, can you go through the Chinese localization files and add to FAILED_CONNECTION_NOTIFICATION and SLOW_CONNECTION_NOTIFICATION? I'll update my PR with your changes.

[coveralls]

Pull Request Test Coverage Report for Build 941

• 31 of 34 (91.18%) changed or added relevant lines in 11 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+1.1%) to 54.201%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
packages/component/src/Activity/SendStatus.js	0	1	0.0%
packages/core/src/reducers/connectivityStatus.js	12	14	85.71%

Totals
Change from base Build 937:	1.1%
Covered Lines:	923
Relevant Lines:	1552

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💛 - Coveralls

[cwhitten]

@corinagum can you provide some screenshots in the descriptions of the pull request? thanks.

[tonyanziano]

Found one missing semicolon, but other than that looks good!

[cwhitten]

@mewa1024 @DesignPolice given that WebChat isn't a public facing name given to the Chat window, should we make the copy more generic? Take BuzzFeed's recent Zo bot. It would be odd to see "WebChat" in error/warning copy here. But I could imagine more generic copy that doesn't call out WebChat specifically.

[mewa1024]

@cwhitten Good point. How about changing the messages to "Taking longer than usual to connect" and "Unable to connect"? @DesignPolice, thoughts?

[DesignPolice]

@cwhitten @mewa1024 @corinagum - That is true Chris, I forget that we need to be more generic with so many different uses of our product. That seems fine to me Mewa.

[corinagum]

I'll update the copy shortly!

[corinagum]

Update: I've updated the copy and fixed the build, but I'm having trouble getting tests to run locally so that I can update the png's for the ConnectivityStatus tests. Will check back in a bit.