Composer update symfony/symfony from 2.7.7 => 2.7.18
Composer update symfony/symfony from 2.7.7 => 2.7.18

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Updating dependencies (including require-dev)
  - Installing symfony/polyfill-mbstring (v1.2.0)
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  - Installing symfony/polyfill-apcu (v1.2.0)
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  - Installing paragonie/random_compat (v1.4.1)
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  - Removing symfony/symfony (v2.7.7)
  - Installing symfony/symfony (v2.7.18)
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paragonie/random_compat suggests installing ext-libsodium (Provides a modern crypto API that can be used to generate random bytes.)
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OpenConext/OpenConext-profile,OpenConext/OpenConext-profile,OpenConext/OpenConext-profile