Fix listDevices() interfering with subsequent operations

[jspyro]

Executing readWord() also in empty deviceList cases. This fixes the issue with subsequent operations failing due to the leftover word in the stream.

100

[coveralls]

Pull Request Test Coverage Report for Build 409

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.02%) to 82.654%

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Totals
Change from base Build 403:	0.02%
Covered Lines:	953
Relevant Lines:	1153

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💛 - Coveralls

[sjamesr]

I'm really sorry I missed this pull request, apparently I didn't have github notifications turned on. Taking a look now.