some corretions in composer installation commands

                     
|Q            |A    |
|---          |---  |
|Bug Fix?     |yes  |
|New Feature? |no   |
|BC Breaks?   |no   |
|Deprecations?|no   |
|Tests Pass?  |yes  |
|Fixed Tickets|#1227|
|License      |BSD  |
|Doc PR       |     |
                     
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The dev stability is required as the skeleton app is not tagged