Fix return for blockGlobal

* Fixed detection of return value
* Fixes #74
9 jobs for globalBlock-bug in 2 minutes and 35 seconds (queued for 1 second)
Status Job ID Name Coverage
  Lint
passed #5809
lint:lint-php5.4

00:00:46

passed #5810
lint:lint-php5.6

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passed #5811
lint:lint-php7.0

00:00:45

passed #5812
lint:lint-php7.1

00:00:47

 
  Codesniffer
passed #5813
codesniffer

00:00:50

 
  Unit
passed #5814
unit:testBasic

00:00:56

passed #5815
unit:testRead

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passed #5816
unit:testReadAssertFail

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passed #5817
unit:testUserProperty

00:00:56