CloudFormation wrapper panics are reported as failures (closes #172)

[aidansteele]

Issue #172

If a CloudFormation custom resource function panics, we send a FAILED status to cfn. Panics are not recovered, as this would cause the stacktrace to be lost before being handled here:

aws-lambda-go/lambda/function.go

Lines 26 to 34 in 02a038f

	if err := recover(); err != nil {
	panicInfo := getPanicInfo(err)
	response.Error = &messages.InvokeResponse_Error{
	Message: panicInfo.Message,
	Type: getErrorType(err),
	StackTrace: panicInfo.StackTrace,
	ShouldExit: true,
	}
	}

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[codecov-io]

Codecov Report

Merging #174 into master will increase coverage by 0.3%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master     #174     +/-   ##
=========================================
+ Coverage   70.02%   70.33%   +0.3%     
=========================================
  Files          18       18             
  Lines         684      691      +7     
=========================================
+ Hits          479      486      +7     
  Misses        165      165             
  Partials       40       40

Impacted Files	Coverage Δ
cfn/wrap.go	92.59% <100%> (+2.59%)	⬆️

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[bmoffatt]

Thanks!