allow "nothing" returns for evalscript

[aviks]

Without this, a method error is thrown when evalscript has an empty return

[codecov]

Codecov Report

Attention: Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.

Project coverage is 82.60%. Comparing base (13d925a) to head (9948c17).

Files	Patch %	Lines
src/client.jl	66.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #110      +/-   ##
==========================================
- Coverage   82.76%   82.60%   -0.16%     
==========================================
  Files           9        9              
  Lines         412      414       +2     
==========================================
+ Hits          341      342       +1     
- Misses         71       72       +1     

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[tanmaykm]

Something like evalscript(conn, "return {10,20}", 0, [1,2]) still fails. Not sure whether we need to convert the response to string at all.

[tanmaykm]

Was discussing this with @aviks. I will add a commit here, removing the conversion step. Will also add some tests.

[jkaye2012]

Similar to the other pending change, this would be a breaking change that requires a major version bump. That isn't necessarily a problem, but if we're going to be making breaking changes, we should bundle them up together and make them all at once.

[tanmaykm]

Yes, I think we can plan a release only after we get both those changes in.
And since we will be doing a major version bump, #109 can be considered ready to review/merge too.

[tanmaykm]

I guess we can merge this now? Will do in a bit.